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Cisco Security Advisory: Cisco IOS Software Internet Key Exchange Resource Exhaustion Vulnerability
by Cisco Systems Product Security Incident Response Team 23 Sep '09

23 Sep '09

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Cisco Security Advisory: Cisco IOS Software Internet Key Exchange Resource Exhaustion Vulnerability Advisory ID: cisco-sa-20090923-ipsec Revision 1.0 For Public Release 2009 September 23 +--------------------------------------------------------------------- Summary ======= Cisco IOS� devices that are configured for Internet Key Exchange (IKE) protocol and certificate based authentication are vulnerable to a resource exhaustion attack. Successful exploitation of this vulnerability may result in the allocation of all available Phase 1 security associations (SA) and prevent the establishment of new IPsec sessions. Cisco has released free software updates that address this vulnerability. This advisory is posted at: http://www.cisco.com/warp/public/707/cisco-sa-20090923-ipsec.shtml Note: The September 23, 2009, Cisco IOS Security Advisory bundled publication includes eleven Security Advisories. Ten of the advisories address vulnerabilities in Cisco IOS Software, and one advisory addresses a vulnerability in Cisco Unified Communications Manager. Each advisory lists the releases that correct the vulnerability or vulnerabilities detailed in the advisory. The following table lists releases that correct all Cisco IOS Software vulnerabilities that have been published on September 23, 2009, or earlier. http://www.cisco.com/warp/public/707/cisco-sa-20090923-bundle.shtml Individual publication links are in "Cisco Event Response: Semiannual Cisco IOS Software Advisory Bundled Publication" at the following link: http://www.cisco.com/web/about/security/intelligence/Cisco_ERP_sep09.html Affected Products ================= Cisco IOS devices that are configured for IKE and certificate based authentication are affected. Vulnerable Products +------------------ IKE is enabled by default if IPsec is used. Cisco IOS devices that are configured for IKE will listen on UDP port 500, UDP port 4500 if the device is configured for NAT Traversal (NAT-T), or UDP ports 848 or 4848 if the device is configured for Group Domain of Interpretation (GDOI). The following outputs show a router that is listening on UDP port 500: Router#show ip sockets Proto Remote Port Local Port In Out Stat TTY OutputIF .... 17 --listen-- 192.168.66.129 500 0 0 11 0 .... Or Router-#show udp Proto Remote Port Local Port In Out Stat TTY OutputIF 17 --listen-- 192.0.2.1 500 0 0 1011 0 17(v6) --listen-- --any-- 500 0 0 20011 0 Router# IKE configurations that are performing certificate based authentication will display "Rivest-Shamir-Adleman Signature" as the authentication method in the output of the "show crypto isakmp policy" command. This output is shown in the following example: Router#show crypto isakmp policy Global IKE policy Default protection suite encryption algorithm: DES - Data Encryption Standard (56 bit keys). hash algorithm: Secure Hash Standard authentication method: Rivest-Shamir-Adleman Signature Diffie-Hellman group: #1 (768 bit) lifetime: 86400 seconds, no volume limit To determine the Cisco IOS Software release that is running on a Cisco product, administrators can log in to the device and issue the "show version" command to display the system banner. The system banner confirms that the device is running Cisco IOS Software by displaying text similar to "Cisco Internetwork Operating System Software" or "Cisco IOS Software." The image name displays in parentheses, followed by "Version" and the Cisco IOS Software release name. Other Cisco devices do not have the "show version" command or may provide different output. The following example identifies a Cisco 6500 Series device that is running Cisco IOS Software release 12.2(18)SXF7 with an installed image name of s72033_rp-IPSERVICESK9_WAN-M: Router#show version Cisco Internetwork Operating System Software IOS (tm) s72033_rp Software (s72033_rp-IPSERVICESK9_WAN-M), Version 12.2(18)SXF7, RELEASE SOFTWARE (fc1) Technical Support: http://www.cisco.com/techsupport Copyright �) 1986-2006 by cisco Systems, Inc. Compiled Thu 23-Nov-06 06:42 by kellythw <output truncated> Additional information about Cisco IOS Software release naming conventions is available in "White Paper: Cisco IOS Reference Guide" at the following link: http://www.cisco.com/warp/public/620/1.html Products Confirmed Not Vulnerable +-------------------------------- Cisco IOS XR Software is not affected by this vulnerability. No other Cisco products are currently known to be affected by this vulnerability. Details ======= IPsec is an IP security feature that provides robust authentication and encryption of IP packets. IKE is a key management protocol standard that is used in conjunction with the IPsec standard. IKE is a hybrid protocol that implements the Oakley and SKEME key exchanges inside the Internet Security Association and Key Management Protocol (ISAKMP) framework. (ISAKMP, Oakley, and SKEME are security protocols that are implemented by IKE.). More information on IKE is available at the following link: http://www.cisco.com/en/US/docs/ios/12_1/security/configuration/guide/scdik… A vulnerability exists in the IKE implementation of Cisco IOS Software, if the certificate based authentication method is used. Successful exploitation of this vulnerability may result in the allocation of all available Phase 1 SAs, which may prevent new IPSec sessions from being established. Administrators can view Phase 1 SAs that are allocated as a result of exploitation by issuing the "show crypto isakmp sa" command. The following example displays sample output for this command: Router#show crypto isakmp sa IPv4 Crypto ISAKMP SA dst src state conn-id slot status 10.48.66.77 10.48.66.6 MM_KEY_EXCH 1004 ACTIVE 10.48.66.77 10.48.66.6 MM_KEY_EXCH 1003 ACTIVE 10.48.66.77 10.48.66.6 MM_KEY_EXCH 1002 ACTIVE .... Any allocated SA can be de-allocated up manually by using the "clear crypto isakmp <conn-ID>" command. This vulnerability is addressed by the Cisco Bug IDs CSCsy07555 and CSCee72997 and has been assigned Common Vulnerabilities and Exposures (CVE) ID CVE-2009-2868. Vulnerability Scoring Details ============================= Cisco has provided scores for the vulnerabilities in this advisory based on the Common Vulnerability Scoring System (CVSS). The CVSS scoring in this Security Advisory is done in accordance with CVSS version 2.0. CVSS is a standards-based scoring method that conveys vulnerability severity and helps determine urgency and priority of response. Cisco has provided a base and temporal score. Customers can then compute environmental scores to assist in determining the impact of the vulnerability in individual networks. Cisco has provided an FAQ to answer additional questions regarding CVSS at: http://www.cisco.com/web/about/security/intelligence/cvss-qandas.html Cisco has also provided a CVSS calculator to help compute the environmental impact for individual networks at: http://intellishield.cisco.com/security/alertmanager/cvss CSCsy07555 - P1 SA stuck in KEY_EXCH forever CVSS Base Score - 7.8 Access Vector - Network Access Complexity - Low Authentication - None Confidentiality Impact - None Integrity Impact - None Availability Impact - Complete CVSS Temporal Score - 6.4 Exploitability - Functional Remediation Level - Official-Fix Report Confidence - Confirmed CSCee72997 - P1 SA stuck in KEY_EXCH forever CVSS Base Score - 7.8 Access Vector - Network Access Complexity - Low Authentication - None Confidentiality Impact - None Integrity Impact - None Availability Impact - Complete CVSS Temporal Score - 6.4 Exploitability - Functional Remediation Level - Official-Fix Report Confidence - Confirmed Impact ====== Successful exploitation of this vulnerability may result in the allocation of all available Phase 1 SAs, which may prevent new IPsec sessions from being established. Software Versions and Fixes =========================== When considering software upgrades, also consult: http://www.cisco.com/go/psirt and any subsequent advisories to determine exposure and a complete upgrade solution. In all cases, customers should exercise caution to be certain the devices to be upgraded contain sufficient memory and that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, contact the Cisco Technical Assistance Center (TAC) or your contracted maintenance provider for assistance. Each row of the Cisco IOS software table (below) names a Cisco IOS release train. If a given release train is vulnerable, then the earliest possible releases that contain the fix (along with the anticipated date of availability for each, if applicable) are listed in the "First Fixed Release" column of the table. The "Recommended Release" column indicates the releases which have fixes for all the published vulnerabilities at the time of this Advisory. A device running a release in the given train that is earlier than the release in a specific column (less than the First Fixed Release) is known to be vulnerable. Cisco recommends upgrading to a release equal to or later than the release in the "Recommended Releases" column of the table. +-------------------------------------------------------------------+ | Major | Availability of Repaired Releases | | Release | | |------------+------------------------------------------------------| | Affected | | Recommended | | 12.0-Based | First Fixed Release | Release | | Releases | | | |-------------------------------------------------------------------| | There are no affected 12.0 based releases | |-------------------------------------------------------------------| | Affected | | Recommended | | 12.1-Based | First Fixed Release | Release | | Releases | | | |-------------------------------------------------------------------| | There are no affected 12.1 based releases | |-------------------------------------------------------------------| | Affected | | Recommended | | 12.2-Based | First Fixed Release | Release | | Releases | | | |------------+---------------------------------------+--------------| | 12.2 | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2B | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2BC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2BW | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2BX | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2BY | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2BZ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2CX | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2CY | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2CZ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2DA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2DD | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2DX | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2EW | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2EWA | Not Vulnerable | | |------------+---------------------------------------+--------------| | | Releases prior to 12.2(44)EX are | 12.2(50)SE3 | | | vulnerable, release 12.2(44)EX and | | | 12.2EX | later are not vulnerable; migrate to | 12.2(52)SE; | | | any release in 12.2SEG | Available on | | | | 13-OCT-2009 | |------------+---------------------------------------+--------------| | 12.2EY | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2EZ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2FX | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2FY | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2FZ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2IRA | Vulnerable; first fixed in 12.2SRD | 12.2(33)SRD3 | |------------+---------------------------------------+--------------| | 12.2IRB | Vulnerable; first fixed in 12.2SRD | 12.2(33)SRD3 | |------------+---------------------------------------+--------------| | | Vulnerable; Contact your support | | | 12.2IRC | organization per the instructions in | | | | Obtaining Fixed Software section of | | | | this advisory | | |------------+---------------------------------------+--------------| | 12.2IXA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2IXB | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2IXC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2IXD | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2IXE | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2IXF | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2IXG | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2IXH | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2JA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2JK | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2MB | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2MC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2S | Not Vulnerable | | |------------+---------------------------------------+--------------| | | | 12.2(31)SB16 | | 12.2SB | 12.2(33)SB6 | | | | | 12.2(33)SB7 | |------------+---------------------------------------+--------------| | 12.2SBC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SCA | Vulnerable; first fixed in 12.2SCB | 12.2(33)SCB4 | |------------+---------------------------------------+--------------| | 12.2SCB | 12.2(33)SCB4 | 12.2(33)SCB4 | |------------+---------------------------------------+--------------| | | | 12.2(50)SE3 | | | 12.2(50)SE3 | | | 12.2SE | | 12.2(52)SE; | | | 12.2(52)SE; Available on 13-OCT-2009 | Available on | | | | 13-OCT-2009 | |------------+---------------------------------------+--------------| | 12.2SEA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SEB | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SEC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SED | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SEE | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SEF | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SEG | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SG | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SGA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SL | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SM | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SO | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SQ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SRA | Vulnerable; first fixed in 12.2SRD | 12.2(33)SRD3 | |------------+---------------------------------------+--------------| | 12.2SRB | Vulnerable; first fixed in 12.2SRD | 12.2(33)SRD3 | |------------+---------------------------------------+--------------| | 12.2SRC | 12.2(33)SRC5; Available on | 12.2(33)SRD3 | | | 29-OCT-2009 | | |------------+---------------------------------------+--------------| | | 12.2(33)SRD3 | | | 12.2SRD | | 12.2(33)SRD3 | | | 12.2(33)SRD2a | | |------------+---------------------------------------+--------------| | 12.2STE | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SU | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SV | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SVA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SVC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SVD | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SVE | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SW | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SX | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SXA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SXB | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SXD | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SXE | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SXF | Not Vulnerable | | |------------+---------------------------------------+--------------| | | 12.2(33)SXH6; Available on | 12.2(33) | | | 30-OCT-2009 | SXH6; | | 12.2SXH | | Available on | | | Please see IOS Software Modularity | 30-OCT-2009 | | | Patch | | |------------+---------------------------------------+--------------| | 12.2SXI | 12.2(33)SXI2a | 12.2(33) | | | | SXI2a | |------------+---------------------------------------+--------------| | 12.2SY | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2SZ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2T | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2TPC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XB | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XD | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XE | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XF | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XG | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XH | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XI | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XJ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XK | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XL | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XM | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XNA | Please see Cisco IOS-XE Software | | | | Availability | | |------------+---------------------------------------+--------------| | 12.2XNB | Please see Cisco IOS-XE Software | | | | Availability | | |------------+---------------------------------------+--------------| | 12.2XNC | Please see Cisco IOS-XE Software | | | | Availability | | |------------+---------------------------------------+--------------| | 12.2XND | Please see Cisco IOS-XE Software | | | | Availability | | |------------+---------------------------------------+--------------| | 12.2XO | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XQ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XR | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XS | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XT | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XU | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XV | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2XW | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YB | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YD | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YE | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YF | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YG | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YH | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YJ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YK | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YL | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YM | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YN | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YO | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YP | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YQ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YR | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YS | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YT | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YU | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YV | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YW | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YX | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YY | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2YZ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2ZA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2ZB | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2ZC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2ZD | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2ZE | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2ZF | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2ZG | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2ZH | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2ZJ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2ZL | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2ZP | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2ZU | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2ZX | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2ZY | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.2ZYA | Not Vulnerable | | |------------+---------------------------------------+--------------| | Affected | | Recommended | | 12.3-Based | First Fixed Release | Release | | Releases | | | |------------+---------------------------------------+--------------| | 12.3 | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3B | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3BC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3BW | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3EU | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3JA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3JEA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3JEB | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3JEC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3JK | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3JL | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3JX | Not Vulnerable | | |------------+---------------------------------------+--------------| | | Vulnerable; first fixed in 12.4 | 12.4(25b) | | 12.3T | | | | | Releases up to and including 12.3(8) | 12.4(23b) | | | T11 are not vulnerable. | | |------------+---------------------------------------+--------------| | 12.3TPC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3VA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XB | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XD | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XE | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XF | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XG | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XI | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XJ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XK | Not Vulnerable | | |------------+---------------------------------------+--------------| | | | 12.4(20)T4 | | | | | | | | 12.4(22)T3 | | 12.3XL | Vulnerable; first fixed in 12.4T | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | 12.3XQ | Not Vulnerable | | |------------+---------------------------------------+--------------| | | | 12.4(25b) | | 12.3XR | Vulnerable; first fixed in 12.4 | | | | | 12.4(23b) | |------------+---------------------------------------+--------------| | | | 12.4(25b) | | 12.3XS | Vulnerable; first fixed in 12.4 | | | | | 12.4(23b) | |------------+---------------------------------------+--------------| | 12.3XU | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XW | Not Vulnerable | | |------------+---------------------------------------+--------------| | | | 12.4(25b) | | 12.3XX | Vulnerable; first fixed in 12.4 | | | | | 12.4(23b) | |------------+---------------------------------------+--------------| | 12.3XY | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XZ | Not Vulnerable | | |------------+---------------------------------------+--------------| | | | 12.4(25b) | | 12.3YA | Vulnerable; first fixed in 12.4 | | | | | 12.4(23b) | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.3YD | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | Vulnerable; migrate to any release in | 12.4(15)XR7 | | 12.3YF | 12.4XN | | | | | 12.4(22)XR | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.3YG | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.3YH | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.3YI | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | 12.3YJ | Not Vulnerable | | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.3YK | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | 12.3YM | Not Vulnerable | | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.3YQ | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.3YS | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.3YT | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.3YU | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | Vulnerable; migrate to any release in | 12.4(15)XR7 | | 12.3YX | 12.4XN | | | | | 12.4(22)XR | |------------+---------------------------------------+--------------| | | Vulnerable; Contact your support | | | 12.3YZ | organization per the instructions in | | | | Obtaining Fixed Software section of | | | | this advisory | | |------------+---------------------------------------+--------------| | 12.3ZA | Not Vulnerable | | |------------+---------------------------------------+--------------| | Affected | | Recommended | | 12.4-Based | First Fixed Release | Release | | Releases | | | |------------+---------------------------------------+--------------| | | Releases prior to 12.4(7) are | 12.4(25b) | | 12.4 | vulnerable; Releases 12.4(7a) and | | | | later are not vulnerable. | 12.4(23b) | |------------+---------------------------------------+--------------| | 12.4GC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JDA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JDC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JDD | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JK | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JL | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JMA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JMB | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JX | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4MD | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4MDA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4MR | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4SW | Not Vulnerable | | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | 12.4(4)T8 | 12.4(20)T4 | | | | | | 12.4T | 12.4(9)T | 12.4(22)T3 | | | | | | | 12.4(6)T1 | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.4XA | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.4XB | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.4XC | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.4XD | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | 12.4XE | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XF | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XG | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XJ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XK | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XL | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XM | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XN | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XP | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XQ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XR | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XT | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XV | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XW | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XY | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XZ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4YA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4YB | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4YD | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4YE | Not Vulnerable | | +-------------------------------------------------------------------+ Cisco IOS XE Software +-------------------- +-------------------------------------------------------------------+ | Cisco IOS XE Software Release | First Fixed Release | |---------------------------------------+---------------------------| | 2.1.x | 2.3.0t | |---------------------------------------+---------------------------| | 2.2.x | 2.3.0t | |---------------------------------------+---------------------------| | 2.3.x | Not Vulnerable | |---------------------------------------+---------------------------| | 2.4.x | Not Vulnerable | +-------------------------------------------------------------------+ Cisco IOS Software Modularity - Maintenance Packs +------------------------------------------------ Customers who are using Cisco IOS Software Modularity can apply the respective maintenance packs. More information on Cisco IOS Software Modularity can be found at the following link: http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps708/prod_bulle… The Maintenance Packs listed below can be downloaded at: http://www.cisco.com/go/pn Cisco IOS Software Modularity Maintenance Pack for 12.2SXH +--------------------------------------------------------- +-------------------------------------------------------------------+ | Cisco IOS Software Release | Solution Maintenance Pack(MP) | |-------------------------------+-----------------------------------| | 12.2(33)SXH3 | MP003 | |-------------------------------+-----------------------------------| | 12.2(33)SXH4 | MP002 | |-------------------------------+-----------------------------------| | 12.2(33)SXH5 | MP001 | +-------------------------------------------------------------------+ Workarounds =========== There are no workarounds for this vulnerability. Additional mitigations that can be deployed on Cisco devices in the network are available in the Cisco Applied Mitigation Bulletin companion document for this advisory, which is available at the following link: http://www.cisco.com/warp/public/707/cisco-amb-20090923-ipsec.shtml Obtaining Fixed Software ======================== Cisco has released free software updates that address these vulnerabilities. Prior to deploying software, customers should consult their maintenance provider or check the software for feature set compatibility and known issues specific to their environment. Customers may only install and expect support for the feature sets they have purchased. By installing, downloading, accessing or otherwise using such software upgrades, customers agree to be bound by the terms of Cisco's software license terms found at: http://www.cisco.com/en/US/docs/general/warranty/English/EU1KEN_.html or as otherwise set forth at Cisco.com Downloads at: http://www.cisco.com/public/sw-center/sw-usingswc.shtml Do not contact psirt(a)cisco.com or security-alert(a)cisco.com for software upgrades. Customers with Service Contracts +------------------------------- Customers with contracts should obtain upgraded software through their regular update channels. For most customers, this means that upgrades should be obtained through the Software Center on Cisco's worldwide website at http://www.cisco.com. Customers using Third Party Support Organizations +------------------------------------------------ Customers whose Cisco products are provided or maintained through prior or existing agreements with third-party support organizations, such as Cisco Partners, authorized resellers, or service providers should contact that support organization for guidance and assistance with the appropriate course of action in regards to this advisory. The effectiveness of any workaround or fix is dependent on specific customer situations, such as product mix, network topology, traffic behavior, and organizational mission. Due to the variety of affected products and releases, customers should consult with their service provider or support organization to ensure any applied workaround or fix is the most appropriate for use in the intended network before it is deployed. Customers without Service Contracts +---------------------------------- Customers who purchase direct from Cisco but do not hold a Cisco service contract, and customers who purchase through third-party vendors but are unsuccessful in obtaining fixed software through their point of sale should acquire upgrades by contacting the Cisco Technical Assistance Center (TAC). TAC contacts are as follows. * +1 800 553 2447 (toll free from within North America) * +1 408 526 7209 (toll call from anywhere in the world) * e-mail: tac(a)cisco.com Customers should have their product serial number available and be prepared to give the URL of this notice as evidence of entitlement to a free upgrade. Free upgrades for non-contract customers must be requested through the TAC. Refer to: http://www.cisco.com/en/US/support/tsd_cisco_worldwide_contacts.html for additional TAC contact information, including localized telephone numbers, and instructions and e-mail addresses for use in various languages. Exploitation and Public Announcements ===================================== The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerability described in this advisory. This vulnerability was reported to Cisco by a customer. Status of this Notice: FINAL ============================ THIS DOCUMENT IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF THE INFORMATION ON THE DOCUMENT OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME. A stand-alone copy or Paraphrase of the text of this document that omits the distribution URL in the following section is an uncontrolled copy, and may lack important information or contain factual errors. Distribution ============ This advisory is posted on Cisco's worldwide website at: http://www.cisco.com/warp/public/707/cisco-sa-20090923-ipsec.shtml In addition to worldwide web posting, a text version of this notice is clear-signed with the Cisco PSIRT PGP key and is posted to the following e-mail and Usenet news recipients. * cust-security-announce(a)cisco.com * first-bulletins(a)lists.first.org * bugtraq(a)securityfocus.com * vulnwatch(a)vulnwatch.org * cisco(a)spot.colorado.edu * cisco-nsp(a)puck.nether.net * full-disclosure(a)lists.grok.org.uk * comp.dcom.sys.cisco(a)newsgate.cisco.com Future updates of this advisory, if any, will be placed on Cisco's worldwide website, but may or may not be actively announced on mailing lists or newsgroups. Users concerned about this problem are encouraged to check the above URL for any updates. Revision History ================ +----------------------------------------+ | Revision | | Initial | | 1.0 | 2009-September-23 | public | | | | release | +----------------------------------------+ Cisco Security Procedures ========================= Complete information on reporting security vulnerabilities in Cisco products, obtaining assistance with security incidents, and registering to receive security information from Cisco, is available on Cisco's worldwide website at: http://www.cisco.com/en/US/products/products_security_vulnerability_policy.… This includes instructions for press inquiries regarding Cisco security notices. All Cisco security advisories are available at: http://www.cisco.com/go/psirt -----BEGIN PGP SIGNATURE----- iD8DBQFKukGS86n/Gc8U/uARAra6AJ0TewwCLaVWd9M++iaztx1+pEWi6QCfdP8l OST6ldrzEu8BBhfiZe0wApg= =9J0c -----END PGP SIGNATURE-----

1 0

Cisco Security Advisory: Cisco IOS Software Network Time Protocol Packet Vulnerability
by Cisco Systems Product Security Incident Response Team 23 Sep '09

23 Sep '09

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Cisco Security Advisory: Cisco IOS Software Network Time Protocol Packet Vulnerability Advisory ID: cisco-sa-20090923-ntp Revision 1.0 For Public Release 2009 September 23 +--------------------------------------------------------------------- Summary ======= Cisco IOS� Software with support for Network Time Protocol (NTP) version (v4) contains a vulnerability processing specific NTP packets that will result in a reload of the device. This results in a remote denial of service (DoS) condition on the affected device. Cisco has released free software updates that address this vulnerability. Workarounds that mitigate this vulnerability are available. This advisory is posted at: http://www.cisco.com/warp/public/707/cisco-sa-20090923-ntp.shtml Note: The September 23, 2009, Cisco IOS Security Advisory bundled publication includes eleven Security Advisories. Ten of the advisories address vulnerabilities in Cisco IOS Software, and one advisory addresses a vulnerability in Cisco Unified Communications Manager. Each advisory lists the releases that correct the vulnerability or vulnerabilities detailed in the advisory. The following table lists releases that correct all Cisco IOS Software vulnerabilities that have been published on September 23, 2009, or earlier. http://www.cisco.com/warp/public/707/cisco-sa-20090923-bundle.shtml Individual publication links are in "Cisco Event Response: Semiannual Cisco IOS Software Advisory Bundled Publication" at the following link: http://www.cisco.com/web/about/security/intelligence/Cisco_ERP_sep09.html Affected Products ================= Vulnerable Products +------------------ Cisco IOS Software devices are vulnerable if they support NTPv4 and are configured for NTP operations. NTP is not enabled in Cisco IOS Software by default. To see if a device supports NTPv4, log into the device and via configuration mode of the command line interface (CLI), enter the command "ntp peer 127.0.0.1 version ?". If the output has the number "4" as an option, then the device supports NTPv4. The following example identifies a Cisco device that is running a Cisco IOS Software release that does support NTPv4: Router#configure terminal Router(config)#ntp peer 127.0.0.1 version ? <2-4> NTP version number The following example identifies a Cisco device that is running a Cisco IOS Software release that does not support NTPv4: Router(config)#ntp peer 127.0.0.1 version ? <1-3> NTP version number To see if a device is configured with NTP, log into the device and issue the CLI command "show running-config | include ntp". If the output returns either of the following commands listed then the device is vulnerable: ntp master <any following commands> ntp peer <any following commands> ntp server <any following commands> ntp broadcast client ntp multicast client The following example identifies a Cisco device that is configured with NTP: router#show running-config | include ntp ntp peer 192.168.0.12 The following example identifies a Cisco device that is not configured with NTP: router#show running-config | include ntp router# To determine the Cisco IOS Software release that is running on a Cisco product, administrators can log in to the device and issue the "show version" command to display the system banner. The system banner confirms that the device is running Cisco IOS Software by displaying text similar to "Cisco Internetwork Operating System Software" or "Cisco IOS Software." The image name displays in parentheses, followed by "Version" and the Cisco IOS Software release name. Other Cisco devices do not have the "show version" command or may provide different output. The following example identifies a Cisco product that is running Cisco IOS Software Release 12.3(26) with an installed image name of C2500-IS-L: Router#show version Cisco Internetwork Operating System Software IOS (tm) 2500 Software (C2500-IS-L), Version 12.3(26), RELEASE SOFTWARE (fc2) Technical Support: http://www.cisco.com/techsupport Copyright �) 1986-2008 by cisco Systems, Inc. Compiled Mon 17-Mar-08 14:39 by dchih <output truncated> The following example shows a product that is running Cisco IOS Software release 12.4(20)T with an image name of C1841-ADVENTERPRISEK9-M: Router#show version Cisco IOS Software, 1841 Software (C1841-ADVENTERPRISEK9-M), Version 12.4(20)T, RELEASE SOFTWARE (fc3) Technical Support: http://www.cisco.com/techsupport Copyright �) 1986-2008 by Cisco Systems, Inc. Compiled Thu 10-Jul-08 20:25 by prod_rel_team <output truncated> Additional information about Cisco IOS Software release naming conventions is available in "White Paper: Cisco IOS Reference Guide" at the following link: http://www.cisco.com/warp/public/620/1.html Products Confirmed Not Vulnerable +-------------------------------- The following products and features are not affected by this vulnerability: * Cisco IOS Software devices without support for NTPv4 * Cisco IOS Software devices configured with only Simple NTP (SNTP) feature * Cisco IOS XE Software * Cisco IOS XR Software No other Cisco products are currently known to be affected by this vulnerability. Details ======= The Network Time Protocol (NTP) is a protocol designed to time-synchronize a network of machines. NTP runs over UDP, which in turn runs over IP. NTPv3 is documented in RFC1305 leavingcisco.com . NTPv4 is a significant revision of the NTP standard, and is the current development version, but has not been formalized into an RFC at the time of publication of this advisory. NTPv4 is currently documented in draft-ietf-ntp-ntpv4-proto-11 leavingcisco.com When a Cisco IOS Software device supporting NTPv4 receives a specific NTP packet it will crash while creating the NTP reply packet. The NTP packet can be sent from any remote device, and does not require authentication. Cisco IOS devices supporting NTPv4 and configured with NTP peer authentication are still vulnerable. The device does not have to be explicitly configured for NTPv4 peers. For example a device configured with all NTP peers being explicitly labeled as version 2 would still be vulnerable, as shown in the following example: Router#show running-config | include ntp ntp peer 192.168.0.254 version 2 ntp peer 192.168.0.1 version 2 Router# For further information on the Cisco implementation of NTP, consult the configuration guide "Cisco IOS and NX-OS Software - Performing Basic System Management" at the following link: http://www.cisco.com/en/US/docs/ios/netmgmt/configuration/guide/nm_basic_sy… This vulnerability is documented in the following Cisco Bug IDs: CSCsu24505 and CSCsv75948 and has been assigned the Common Vulnerabilities and Exposures (CVE) identifier CVE-2009-2869. Both Cisco bug IDs are required for a full fix to this vulnerability. Vulnerability Scoring Details ============================= Cisco has provided scores for the vulnerability in this advisory based on the Common Vulnerability Scoring System (CVSS). The CVSS scoring in this Security Advisory is done in accordance with CVSS version 2.0. CVSS is a standards-based scoring method that conveys vulnerability severity and helps determine urgency and priority of response. Cisco has provided a base and temporal score. Customers can then compute environmental scores to assist in determining the impact of the vulnerability in individual networks. Cisco has provided an FAQ to answer additional questions regarding CVSS at: http://www.cisco.com/web/about/security/intelligence/cvss-qandas.html Cisco has also provided a CVSS calculator to help compute the environmental impact for individual networks at: http://intellishield.cisco.com/security/alertmanager/cvss CSCsu24505, CSCsv75948 - Cisco IOS Software NTP Packet Vulnerability CVSS Base Score - 7.8 Access Vector - Network Access Complexity - Low Authentication - None Confidentiality Impact - None Integrity Impact - None Availability Impact - Complete CVSS Temporal Score - 6.4 Exploitability - Functional Remediation Level - Official-Fix Report Confidence - Confirmed Impact ====== Successful exploitation of the vulnerability may result in a reload of the device. The vulnerability could be repeatedly exploited to cause an extended DoS condition. Software Versions and Fixes =========================== When considering software upgrades, also consult: http://www.cisco.com/go/psirt and any subsequent advisories to determine exposure and a complete upgrade solution. In all cases, customers should exercise caution to be certain the devices to be upgraded contain sufficient memory and that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, contact the Cisco Technical Assistance Center (TAC) or your contracted maintenance provider for assistance. Each row of the Cisco IOS software table (below) names a Cisco IOS release train. If a given release train is vulnerable, then the earliest possible releases that contain the fix (along with the anticipated date of availability for each, if applicable) are listed in the "First Fixed Release" column of the table. The "Recommended Release" column indicates the releases which have fixes for all the published vulnerabilities at the time of this Advisory. A device running a release in the given train that is earlier than the release in a specific column (less than the First Fixed Release) is known to be vulnerable. Cisco recommends upgrading to a release equal to or later than the release in the "Recommended Releases" column of the table. +-------------------------------------------------------------------+ | Major | Availability of Repaired Releases | | Release | | |------------+------------------------------------------------------| | Affected | | Recommended | | 12.0-Based | First Fixed Release | Release | | Releases | | | |-------------------------------------------------------------------| | There are no affected 12.0 based releases | |-------------------------------------------------------------------| | Affected | | Recommended | | 12.1-Based | First Fixed Release | Release | | Releases | | | |-------------------------------------------------------------------| | There are no affected 12.1 based releases | |-------------------------------------------------------------------| | Affected | | Recommended | | 12.2-Based | First Fixed Release | Release | | Releases | | | |-------------------------------------------------------------------| | There are no affected 12.2 based releases | |-------------------------------------------------------------------| | Affected | | Recommended | | 12.3-Based | First Fixed Release | Release | | Releases | | | |-------------------------------------------------------------------| | There are no affected 12.3 based releases | |-------------------------------------------------------------------| | Affected | | Recommended | | 12.4-Based | First Fixed Release | Release | | Releases | | | |------------+---------------------------------------+--------------| | 12.4 | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4GC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JDA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JDC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JDD | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JK | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JL | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JMA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JMB | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JX | Not Vulnerable | | |------------+---------------------------------------+--------------| | | Releases prior to 12.4(22)MD are not | | | 12.4MD | vulnerable, vulnerability was first | 12.4(22)MD1 | | | introduced in 12.4(22)MD, first fixed | | | | in 12.4(22)MD1. | | |------------+---------------------------------------+--------------| | 12.4MDA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4MR | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4SW | Not Vulnerable | | |------------+---------------------------------------+--------------| | | Releases prior to 12.4(20)T are not | | | | vulnerable. | | | | | 12.4(20)T4 | | | 12.4(20)T and 12.4(20)T1 are | | | | vulnerable, vulnerability is first | 12.4(22)T3 | | 12.4T | fixed in 12.4(20)T2. | | | | | 12.4(24)T2; | | | 12.4(22)T is vulnerable, | Available on | | | vulnerability is first fixed in 12.4 | 23-OCT-2009 | | | (22)T1 | | | | | | | | 12.4(24)T is not vulnerable. | | |------------+---------------------------------------+--------------| | 12.4XA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XB | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XD | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XE | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XF | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XG | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XJ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XK | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XL | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XM | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XN | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XP | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XQ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XR | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XT | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XV | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XW | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XY | Not Vulnerable | | |------------+---------------------------------------+--------------| | | | 12.4(20)T4 | | | | | | | | 12.4(22)T3 | | 12.4XZ | Vulnerable; first fixed in 12.4T | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | | 12.4(20)T4 | | | | | | | | 12.4(22)T3 | | 12.4YA | Vulnerable; first fixed in 12.4T | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | 12.4YB | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4YD | 12.4(22)YD1 | 12.4(22)YD1 | |------------+---------------------------------------+--------------| | 12.4YE | 12.4(22)YE1 | 12.4(22)YE1 | +-------------------------------------------------------------------+ Workarounds =========== There are no workarounds other than disabling NTP on the device. The following mitigations have been identified for this vulnerability; only packets destined for any configured IP address on the device can exploit this vulnerability. Transit traffic will not exploit this vulnerability. Note: NTP peer authentication is not a workaround and is still a vulnerable configuration. NTP Access Group +--------------- Warning: Because the feature in this vulnerability utilizes UDP as a transport, it is possible to spoof the sender's IP address, which may defeat access control lists (ACLs) that permit communication to these ports from trusted IP addresses. Unicast Reverse Path Forwarding (Unicast RPF) should be considered to be used in conjunction to offer a better mitigation solution. !--- Configure trusted peers for allowed access access-list 1 permit 171.70.173.55 !--- Apply ACE to the NTP configuration ntp access-group 1 For additional information on NTP access control groups, consult the document titled "Performing Basic System Management" at the following link: http://www.cisco.com/en/US/docs/ios/netmgmt/configuration/guide/nm_basic_sy… Infrastructure Access Control Lists +---------------------------------- warning Warning: Because the feature in this vulnerability utilizes UDP as a transport, it is possible to spoof the sender's IP address, which may defeat ACLs that permit communication to these ports from trusted IP addresses. Unicast RPF should be considered to be used in conjunction to offer a better mitigation solution. Although it is often difficult to block traffic that transits a network, it is possible to identify traffic that should never be allowed to target infrastructure devices and block that traffic at the border of networks. Infrastructure ACLs (iACLs) are a network security best practice and should be considered as a long-term addition to good network security as well as a workaround for this specific vulnerability. The iACL example below should be included as part of the deployed infrastructure access-list, which will help protect all devices with IP addresses in the infrastructure IP address range: !--- !--- Feature: Network Time Protocol (NTP) !--- access-list 150 permit udp TRUSTED_SOURCE_ADDRESSES WILDCARD INFRASTRUCTURE_ADDRESSES WILDCARD eq 123 !--- Note: If the router is acting as a NTP broadcast client !--- via the interface command "ntp broadcast client" !--- then broadcast and directed broadcasts must be !--- filtered as well. The following example covers !--- an infrastructure address space of 192.168.0.X access-list 150 permit udp TRUSTED_SOURCE_ADDRESSES WILDCARD host 192.168.0.255 eq ntp access-list 150 permit udp TRUSTED_SOURCE_ADDRESSES WILDCARD host 255.255.255.255 eq ntp !--- Note: If the router is acting as a NTP multicast client !--- via the interface command "ntp multicast client" !--- then multicast IP packets to the mutlicast group must !--- be filtered as well. The following example covers !--- a NTP multicast group of 239.0.0.1 (Default is !--- 224.0.1.1) access-list 150 permit udp TRUSTED_SOURCE_ADDRESSES WILDCARD host 239.0.0.1 eq ntp !--- Deny NTP traffic from all other sources destined !--- to infrastructure addresses. access-list 150 deny udp any INFRASTRUCTURE_ADDRESSES WILDCARD eq 123 !--- Permit/deny all other Layer 3 and Layer 4 traffic in !--- accordance with existing security policies and !--- configurations. Permit all other traffic to transit the !--- device. access-list 150 permit ip any any !--- Apply access-list to all interfaces (only one example !--- shown) interface fastEthernet 2/0 ip access-group 150 in The white paper entitled "Protecting Your Core: Infrastructure Protection Access Control Lists" presents guidelines and recommended deployment techniques for infrastructure protection access lists and is available at the following link: http://www.cisco.com/en/US/tech/tk648/tk361/technologies_white_paper09186a0… Control Plane Policing +--------------------- Warning: Because the feature in this vulnerability utilizes UDP as a transport, it is possible to spoof the sender's IP address, which may defeat ACLs that permit communication to these ports from trusted IP addresses. Unicast RPF should be considered to be used in conjunction to offer a better mitigation solution. Control Plane Policing (CoPP) can be used to block untrusted UDP traffic to the device. Cisco IOS software releases 12.0S, 12.2SX, 12.2S, 12.3T, 12.4, and 12.4T support the CoPP feature. CoPP can be configured on a device to help protect the management and control planes and minimize the risk and effectiveness of direct infrastructure attacks by explicitly permitting only authorized traffic that is sent to infrastructure devices in accordance with existing security policies and configurations. The CoPP example below should be included as part of the deployed CoPP, which will help protect all devices with IP addresses in the infrastructure IP address range. !--- Feature: Network Time Protocol (NTP) access-list 150 deny udp TRUSTED_SOURCE_ADDRESSES WILDCARD any eq 123 !--- Deny NTP traffic from all other sources destined !--- to the device control plane. access-list 150 permit udp any any eq 123 !--- Permit (Police or Drop)/Deny (Allow) all other Layer3 and !--- Layer4 traffic in accordance with existing security policies !--- and configurations for traffic that is authorized to be sent !--- to infrastructure devices !--- Create a Class-Map for traffic to be policed by !--- the CoPP feature class-map match-all drop-udp-class match access-group 150 !--- Create a Policy-Map that will be applied to the !--- Control-Plane of the device. policy-map drop-udp-traffic class drop-udp-class drop !--- Apply the Policy-Map to the !--- Control-Plane of the device control-plane service-policy input drop-udp-traffic In the above CoPP example, the access control list entries (ACEs) that match the potential exploit packets with the "permit" action result in these packets being discarded by the policy-map "drop" function, while packets that match the "deny" action (not shown) are not affected by the policy-map drop function. Please note that the policy-map syntax is different in the 12.2S and 12.0S Cisco IOS Software trains: policy-map drop-udp-traffic class drop-udp-class police 32000 1500 1500 conform-action drop exceed-action drop Additional information on the configuration and use of the CoPP feature can be found in the documents, "Control Plane Policing Implementation Best Practices" and "Cisco IOS Software Releases 12.2 S - Control Plane Policing" at the following links: http://www.cisco.com/web/about/security/intelligence/coppwp_gs.html and http://www.cisco.com/en/US/docs/ios/12_3t/12_3t4/feature/guide/gtrtlimt.html Obtaining Fixed Software ======================== Cisco has released free software updates that address these vulnerabilities. Prior to deploying software, customers should consult their maintenance provider or check the software for feature set compatibility and known issues specific to their environment. Customers may only install and expect support for the feature sets they have purchased. By installing, downloading, accessing or otherwise using such software upgrades, customers agree to be bound by the terms of Cisco's software license terms found at: http://www.cisco.com/en/US/docs/general/warranty/English/EU1KEN_.html or as otherwise set forth at Cisco.com Downloads at: http://www.cisco.com/public/sw-center/sw-usingswc.shtml Do not contact psirt(a)cisco.com or security-alert(a)cisco.com for software upgrades. Customers with Service Contracts +------------------------------- Customers with contracts should obtain upgraded software through their regular update channels. For most customers, this means that upgrades should be obtained through the Software Center on Cisco's worldwide website at http://www.cisco.com. Customers using Third Party Support Organizations +------------------------------------------------ Customers whose Cisco products are provided or maintained through prior or existing agreements with third-party support organizations, such as Cisco Partners, authorized resellers, or service providers should contact that support organization for guidance and assistance with the appropriate course of action in regards to this advisory. The effectiveness of any workaround or fix is dependent on specific customer situations, such as product mix, network topology, traffic behavior, and organizational mission. Due to the variety of affected products and releases, customers should consult with their service provider or support organization to ensure any applied workaround or fix is the most appropriate for use in the intended network before it is deployed. Customers without Service Contracts +---------------------------------- Customers who purchase direct from Cisco but do not hold a Cisco service contract, and customers who purchase through third-party vendors but are unsuccessful in obtaining fixed software through their point of sale should acquire upgrades by contacting the Cisco Technical Assistance Center (TAC). TAC contacts are as follows. * +1 800 553 2447 (toll free from within North America) * +1 408 526 7209 (toll call from anywhere in the world) * e-mail: tac(a)cisco.com Customers should have their product serial number available and be prepared to give the URL of this notice as evidence of entitlement to a free upgrade. Free upgrades for non-contract customers must be requested through the TAC. Refer to: http://www.cisco.com/en/US/support/tsd_cisco_worldwide_contacts.html for additional TAC contact information, including localized telephone numbers, and instructions and e-mail addresses for use in various languages. Exploitation and Public Announcements ===================================== The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerability described in this advisory. This vulnerability was discovered by Cisco when handling customer support calls. Status of this Notice: FINAL ============================ THIS DOCUMENT IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF THE INFORMATION ON THE DOCUMENT OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME. A stand-alone copy or Paraphrase of the text of this document that omits the distribution URL in the following section is an uncontrolled copy, and may lack important information or contain factual errors. Distribution ============ This advisory is posted on Cisco's worldwide website at: http://www.cisco.com/warp/public/707/cisco-sa-20090923-ntp.shtml In addition to worldwide web posting, a text version of this notice is clear-signed with the Cisco PSIRT PGP key and is posted to the following e-mail and Usenet news recipients. * cust-security-announce(a)cisco.com * first-bulletins(a)lists.first.org * bugtraq(a)securityfocus.com * vulnwatch(a)vulnwatch.org * cisco(a)spot.colorado.edu * cisco-nsp(a)puck.nether.net * full-disclosure(a)lists.grok.org.uk * comp.dcom.sys.cisco(a)newsgate.cisco.com Future updates of this advisory, if any, will be placed on Cisco's worldwide website, but may or may not be actively announced on mailing lists or newsgroups. Users concerned about this problem are encouraged to check the above URL for any updates. Revision History ================ +----------------------------------------+ | Revision | | Initial | | 1.0 | 2009-September-23 | public | | | | release | +----------------------------------------+ Cisco Security Procedures ========================= Complete information on reporting security vulnerabilities in Cisco products, obtaining assistance with security incidents, and registering to receive security information from Cisco, is available on Cisco's worldwide website at: http://www.cisco.com/en/US/products/products_security_vulnerability_policy.… This includes instructions for press inquiries regarding Cisco security notices. All Cisco security advisories are available at: http://www.cisco.com/go/psirt -----BEGIN PGP SIGNATURE----- iD8DBQFKukGW86n/Gc8U/uARAjmYAJ0f6SVZp7qLXI0HFG5I0cYzxtFfAACeIvG2 juvYatuemQrQUj8hfg2v0lQ= =KnSP -----END PGP SIGNATURE-----

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Cisco Security Advisory: Cisco IOS Software Session Initiation Protocol Denial of Service Vulnerability
by Cisco Systems Product Security Incident Response Team 23 Sep '09

23 Sep '09

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Cisco Security Advisory: Cisco IOS Software Session Initiation Protocol Denial of Service Vulnerability Advisory ID: cisco-sa-20090923-sip Revision 1.0 For Public Release 2009 September 23 +--------------------------------------------------------------------- Summary ======= A vulnerability exists in the Session Initiation Protocol (SIP) implementation in Cisco IOS� Software that could allow an unauthenticated attacker to cause a denial of service (DoS) condition on an affected device when the Cisco Unified Border Element feature is enabled. Cisco has released free software updates that address this vulnerability. For devices that must run SIP there are no workarounds; however, mitigations are available to limit exposure of the vulnerability. This advisory is posted at: http://www.cisco.com/warp/public/707/cisco-sa-20090923-sip.shtml Note: The September 23, 2009, Cisco IOS Security Advisory bundled publication includes eleven Security Advisories. Ten of the advisories address vulnerabilities in Cisco IOS Software, and one advisory addresses a vulnerability in Cisco Unified Communications Manager. Each advisory lists the releases that correct the vulnerability or vulnerabilities detailed in the advisory. The following table lists releases that correct all Cisco IOS Software vulnerabilities that have been published on September 23, 2009, or earlier. http://www.cisco.com/warp/public/707/cisco-sa-20090923-bundle.shtml Individual publication links are in "Cisco Event Response: Semiannual Cisco IOS Software Advisory Bundled Publication" at the following link: http://www.cisco.com/web/about/security/intelligence/Cisco_ERP_sep09.html Affected Products ================= This vulnerability only affects devices running Cisco IOS Software with SIP voice services enabled. Vulnerable Products +------------------ Cisco devices running affected Cisco IOS Software versions that are configured to process SIP messages with the Cisco Unified Border Element feature are affected. Cisco IOS devices that are not configured for SIP and Cisco Unified Border Element feature are not affected by this vulnerability. Note: Cisco Unified Border Element feature (previously known as the Cisco Multiservice IP-to-IP Gateway) is a special Cisco IOS Software image that runs on Cisco multiservice gateway platforms. It provides a network-to-network interface point for billing, security, call admission control, quality of service, and signaling interworking. Cisco Unified Border Element feature requires the "voice service voip" command and the "allow-connections" subcommand. An example of an affected configuration is as follows: voice service voip allow-connections from-type to to-type ... ! Recent versions of Cisco IOS Software do not process SIP messages by default. Creating a dial peer by issuing the command "dial-peer voice" will start the SIP processes, causing the Cisco IOS device to process SIP messages. In addition, several features within Cisco Unified Communications Manager Express, such as ePhones, once configured will also automatically start the SIP process, which will cause the device to start processing SIP messages. An example of an affected configuration is as follows: dial-peer voice <Voice dial-peer tag> voip ... ! In addition to inspecting the Cisco IOS device configuration for a dial-peer command that causes the device to process SIP messages, administrators can also use the command show processes | include SIP to determine whether Cisco IOS Software is running the processes that handle SIP messages. In the following example, the presence of the processes CCSIP_UDP_SOCKET or CCSIP_TCP_SOCKET indicates that the Cisco IOS device is processing SIP messages: Router#show processes | include SIP 149 Mwe 40F48254 4 1 400023108/24000 0 CCSIP_UDP_SOCKET 150 Mwe 40F48034 4 1 400023388/24000 0 CCSIP_TCP_SOCKET warning Warning: Since there are several ways a device running Cisco IOS Software can start processing SIP messages, it is recommended that the "show processes | include SIP" command be used to determine whether the device is processing SIP messages instead of relying on the presence of specific configuration commands. To determine the Cisco IOS Software release that is running on a Cisco product, administrators can log in to the device and issue the show version command to display the system banner. The system banner confirms that the device is running Cisco IOS Software by displaying text similar to "Cisco Internetwork Operating System Software" or "Cisco IOS Software." The image name displays in parentheses, followed by "Version" and the Cisco IOS Software release name. Other Cisco devices do not have the show version command or may provide different output. The following example identifies a Cisco product that is running Cisco IOS Software Release 12.3(26) with an installed image name of C2500-IS-L: Router#show version Cisco Internetwork Operating System Software IOS (tm) 2500 Software (C2500-IS-L), Version 12.3(26), RELEASE SOFTWARE (fc2) Technical Support: http://www.cisco.com/techsupport Copyright (c) 1986-2008 by cisco Systems, Inc. Compiled Mon 17-Mar-08 14:39 by dchih !--- output truncated The following example identifies a Cisco product that is running Cisco IOS Software Release 12.4(20)T with an installed image name of C1841-ADVENTERPRISEK9-M: Router#show version Cisco IOS Software, 1841 Software (C1841-ADVENTERPRISEK9-M), Version 12.4(20)T, RELEASE SOFTWARE (fc3) Technical Support: http://www.cisco.com/techsupport Copyright (c) 1986-2008 by Cisco Systems, Inc. Compiled Thu 10-Jul-08 20:25 by prod_rel_team !--- output truncated Additional information about Cisco IOS Software release naming conventions is available in "White Paper: Cisco IOS Reference Guide" at the following link: http://www.cisco.com/warp/public/620/1.html Products Confirmed Not Vulnerable +-------------------------------- The SIP Application Layer Gateway (ALG), which is used by the Cisco IOS NAT and firewall features of Cisco IOS Software, is not affected by this vulnerability. Cisco IOS XE Software and Cisco IOS XR Software are not affected by this vulnerability. No other Cisco products are currently known to be affected by this vulnerability. Details ======= SIP is a popular signaling protocol that is used to manage voice and video calls across IP networks such as the Internet. SIP is responsible for handling all aspects of call setup and termination. Voice and video are the most popular types of sessions that SIP handles, but the protocol has the flexibility to accommodate other applications that require call setup and termination. SIP call signaling can use UDP (port 5060), TCP (port 5060), or TLS (TCP port 5061) as the underlying transport protocol. The Cisco Unified Border Element (previously known as the Cisco Multiservice IP-to-IP Gateway) is a special Cisco IOS Software image that runs on Cisco multiservice gateway platforms. It provides a network-to-network interface point for billing, security, call admission control, quality of service, and signaling interworking. For more information about Cisco Unified Border Element refer to the following link: http://www.cisco.com/en/US/products/sw/voicesw/ps5640/index.html A DoS vulnerability exists in the SIP implementation in Cisco IOS Software when devices are running a Cisco IOS image that contains the Cisco Unified Border Element feature. This vulnerability is triggered by processing a series of crafted SIP messages. This vulnerability is documented in Cisco Bug ID CSCsx25880 and has been assigned Common Vulnerabilities and Exposures (CVE) ID CVE-2009-2870. Vulnerability Scoring Details ============================= Cisco has provided scores for the vulnerability in this advisory based on the Common Vulnerability Scoring System (CVSS). The CVSS scoring in this Security Advisory is done in accordance with CVSS version 2.0. CVSS is a standards-based scoring method that conveys vulnerability severity and helps determine urgency and priority of response. Cisco has provided a base and temporal score. Customers can then compute environmental scores to assist in determining the impact of the vulnerability in individual networks. Cisco has provided an FAQ to answer additional questions regarding CVSS at: http://www.cisco.com/web/about/security/intelligence/cvss-qandas.html Cisco has also provided a CVSS calculator to help compute the environmental impact for individual networks at: http://intellishield.cisco.com/security/alertmanager/cvss CSCsx25880 - Crafted SIP packet may cause device reload CVSS Base Score - 7.8 Access Vector - Network Access Complexity - Low Authentication - None Confidentiality Impact - None Integrity Impact - None Availability Impact - Complete CVSS Temporal Score - 6.4 Exploitability - Functional Remediation Level - Official-Fix Report Confidence - Confirmed Impact ====== Successful exploitation of the vulnerability described in this document may result in a reload of the device. The issue could be repeatedly exploited to cause an extended DoS condition. Software Versions and Fixes =========================== When considering software upgrades, also consult: http://www.cisco.com/go/psirt and any subsequent advisories to determine exposure and a complete upgrade solution. In all cases, customers should exercise caution to be certain the devices to be upgraded contain sufficient memory and that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, contact the Cisco Technical Assistance Center (TAC) or your contracted maintenance provider for assistance. Each row of the Cisco IOS Software table (below) names a Cisco IOS release train. If a given release train is vulnerable, then the earliest possible releases that contain the fix (along with the anticipated date of availability for each, if applicable) are listed in the "First Fixed Release" column of the table. The "Recommended Release" column indicates the releases which have fixes for all the published vulnerabilities at the time of this Advisory. A device running a release in the given train that is earlier than the release in a specific column (less than the First Fixed Release) is known to be vulnerable. Cisco recommends upgrading to a release equal to or later than the release in the "Recommended Releases" column of the table. +-------------------------------------------------------------------+ | Major | Availability of Repaired Releases | | Release | | |------------+------------------------------------------------------| | Affected | | Recommended | | 12.0-Based | First Fixed Release | Release | | Releases | | | |-------------------------------------------------------------------| | There are no affected 12.0 based releases. | |-------------------------------------------------------------------| | Affected | | Recommended | | 12.1-Based | First Fixed Release | Release | | Releases | | | |-------------------------------------------------------------------| | There are no affected 12.1 based releases. | |-------------------------------------------------------------------| | Affected | | Recommended | | 12.2-Based | First Fixed Release | Release | | Releases | | | |-------------------------------------------------------------------| | There are no affected 12.2 based releases. | |-------------------------------------------------------------------| | Affected | | Recommended | | 12.3-Based | First Fixed Release | Release | | Releases | | | |------------+---------------------------------------+--------------| | 12.3 | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3B | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3BC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3BW | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3EU | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3JA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3JEA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3JEB | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3JEC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3JK | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3JL | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3JX | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3T | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3TPC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3VA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XB | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XD | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XE | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XF | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XG | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XI | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XJ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XK | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XL | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XQ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XR | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XS | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XU | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XW | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XX | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XY | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3XZ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3YA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3YD | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3YF | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3YG | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3YH | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3YI | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3YJ | Not Vulnerable | | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | Releases prior to 12.3(11)YK3 are | 12.4(20)T4 | | | vulnerable, release 12.3(11)YK3 and | | | 12.3YK | later are not vulnerable; first fixed | 12.4(22)T3 | | | in 12.4T | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | 12.3YM | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3YQ | Not Vulnerable | | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | Vulnerable; first fixed in 12.4T | 12.4(20)T4 | | | | | | 12.3YS | Releases up to and including 12.3(11) | 12.4(22)T3 | | | YS1 are not vulnerable. | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.3YT | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | 12.3YU | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3YX | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3YZ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.3ZA | Not Vulnerable | | |------------+---------------------------------------+--------------| | Affected | | Recommended | | 12.4-Based | First Fixed Release | Release | | Releases | | | |------------+---------------------------------------+--------------| | 12.4 | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4GC | 12.4(24)GC1 | | |------------+---------------------------------------+--------------| | 12.4JA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JDA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JDC | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JDD | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JK | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JL | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JMA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JMB | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4JX | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4MD | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4MDA | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4MR | 12.4(19)MR3 | 12.4(19)MR3 | |------------+---------------------------------------+--------------| | 12.4SW | Not Vulnerable | | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | 12.4(24)T1 | | | | | 12.4(20)T4 | | | 12.4(15)T10 | | | 12.4T | | 12.4(22)T3 | | | 12.4(20)T3 | | | | | 12.4(24)T2; | | | 12.4(22)T2 | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.4XA | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.4XB | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.4XC | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.4XD | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.4XE | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | 12.4XF | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XG | Not Vulnerable | | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.4XJ | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | 12.4XK | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XL | 12.4(15)XL5 | | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | Vulnerable; first fixed in 12.4T | 12.4(20)T4 | | | | | | 12.4XM | Releases up to and including 12.4(15) | 12.4(22)T3 | | | XM are not vulnerable. | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | 12.4XN | Not Vulnerable | | |------------+---------------------------------------+--------------| | | Vulnerable; Contact your support | | | 12.4XP | organization per the instructions in | | | | Obtaining Fixed Software section of | | | | this advisory | | |------------+---------------------------------------+--------------| | 12.4XQ | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4XR | Not Vulnerable | | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.4XT | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | Vulnerable; Contact your support | | | 12.4XV | organization per the instructions in | | | | Obtaining Fixed Software section of | | | | this advisory | | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.4XW | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.4XY | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.4XZ | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | | | 12.4(15)T10 | | | | | | | | 12.4(20)T4 | | | | | | 12.4YA | Vulnerable; first fixed in 12.4T | 12.4(22)T3 | | | | | | | | 12.4(24)T2; | | | | Available on | | | | 23-OCT-2009 | |------------+---------------------------------------+--------------| | 12.4YB | 12.4(22)YB1 | 12.4(22)YB4 | |------------+---------------------------------------+--------------| | 12.4YD | Not Vulnerable | | |------------+---------------------------------------+--------------| | 12.4YE | Not Vulnerable | | +-------------------------------------------------------------------+ Note: No Cisco IOS-XE or Cisco IOS Software Modularity releases are affected by this vulnerability. Workarounds =========== If the affected Cisco IOS device requires SIP for VoIP services, SIP cannot be disabled, and therefore, no workarounds are available. Users are advised to apply mitigation techniques to help limit exposure to the vulnerability. Mitigation consists of allowing only legitimate devices to connect to the routers. To increase effectiveness, the mitigation must be coupled with anti-spoofing measures on the network edge. This action is required because SIP can use UDP as the transport protocol. Additional mitigations that can be deployed on Cisco devices within the network are available in the companion document "Cisco Applied Mitigation Bulletin: Identifying and Mitigating Exploitation of the Denial of Service Vulnerabilities in Cisco Unified Communications Manager and Cisco IOS Software", which is available at the following location: http://www.cisco.com/warp/public/707/cisco-amb-20090923-voice.shtml Disable SIP Listening Ports +-------------------------- For devices that do not require SIP to be enabled, the simplest and most effective workaround is to disable SIP processing on the device. Some versions of Cisco IOS Software allow administrators to accomplish this with the following commands: sip-ua no transport udp no transport tcp no transport tcp tls Warning: When applying this workaround to devices that are processing Media Gateway Control Protocol (MGCP) or H.323 calls, the device will not stop SIP processing while active calls are being processed. Under these circumstances, this workaround should be implemented during a maintenance window when active calls can be briefly stopped. The "show udp connections", "show tcp brief all", and "show processes | include SIP" commands can be used to confirm that the SIP UDP and TCP ports are closed after applying this workaround. Depending on the Cisco IOS Software version in use, the output of "show ip sockets" still showed UDP port 5060 open, but sending something to that port caused the SIP process to emit the following message: *Feb 2 11:36:47.691: sip_udp_sock_process_read: SIP UDP Listener is DISABLED Control Plane Policing +--------------------- For devices that need to offer SIP services it is possible to use Control Plane Policing (CoPP) to block SIP traffic to the device from untrusted sources. Cisco IOS Releases 12.0S, 12.2SX, 12.2S, 12.3T, 12.4, and 12.4T support the CoPP feature. CoPP may be configured on a device to protect the management and control planes to minimize the risk and effectiveness of direct infrastructure attacks by explicitly permitting only authorized traffic sent to infrastructure devices in accordance with existing security policies and configurations. The following example can be adapted to the network !-- The 192.168.1.0/24 network and the 172.16.1.1 host are trusted. !-- Everything else is not trusted. The following access list is used !-- to determine what traffic needs to be dropped by a control plane !-- policy (the CoPP feature.) If the access list matches (permit) !-- then traffic will be dropped and if the access list does not !-- match (deny) then traffic will be processed by the router. access-list 100 deny udp 192.168.1.0 0.0.0.255 any eq 5060 access-list 100 deny tcp 192.168.1.0 0.0.0.255 any eq 5060 access-list 100 deny tcp 192.168.1.0 0.0.0.255 any eq 5061 access-list 100 deny udp host 172.16.1.1 any eq 5060 access-list 100 deny tcp host 172.16.1.1 any eq 5060 access-list 100 deny tcp host 172.16.1.1 any eq 5061 access-list 100 permit udp any any eq 5060 access-list 100 permit tcp any any eq 5060 access-list 100 permit tcp any any eq 5061 !-- Permit (Police or Drop)/Deny (Allow) all other Layer3 and Layer4 !-- traffic in accordance with existing security policies and !-- configurations for traffic that is authorized to be sent !-- to infrastructure devices. !-- Create a Class-Map for traffic to be policed by !-- the CoPP feature. class-map match-all drop-sip-class match access-group 100 !-- Create a Policy-Map that will be applied to the !-- Control-Plane of the device. policy-map drop-sip-traffic class drop-sip-class drop !-- Apply the Policy-Map to the Control-Plane of the !-- device. control-plane service-policy input drop-sip-traffic Warning: Because SIP can use UDP as a transport protocol, it is possible to easily spoof the IP address of the sender, which may defeat access control lists that permit communication to these ports from trusted IP addresses. In the above CoPP example, the access control entries (ACEs) that match the potential exploit packets with the "permit" action result in these packets being discarded by the policy-map "drop" function, while packets that match the "deny" action (not shown) are not affected by the policy-map drop function. Additional information on the configuration and use of the CoPP feature can be found at: http://www.cisco.com/web/about/security/intelligence/coppwp_gs.html and http://www.cisco.com/en/US/docs/ios/12_3t/12_3t4/feature/guide/gtrtlimt.html Obtaining Fixed Software ======================== Cisco has released free software updates that address these vulnerabilities. Prior to deploying software, customers should consult their maintenance provider or check the software for feature set compatibility and known issues specific to their environment. Customers may only install and expect support for the feature sets they have purchased. By installing, downloading, accessing or otherwise using such software upgrades, customers agree to be bound by the terms of Cisco's software license terms found at: http://www.cisco.com/en/US/docs/general/warranty/English/EU1KEN_.html or as otherwise set forth at Cisco.com Downloads at: http://www.cisco.com/public/sw-center/sw-usingswc.shtml Do not contact psirt(a)cisco.com or security-alert(a)cisco.com for software upgrades. Customers with Service Contracts +------------------------------- Customers with contracts should obtain upgraded software through their regular update channels. For most customers, this means that upgrades should be obtained through the Software Center on Cisco's worldwide website at http://www.cisco.com. Customers using Third Party Support Organizations +------------------------------------------------ Customers whose Cisco products are provided or maintained through prior or existing agreements with third-party support organizations, such as Cisco Partners, authorized resellers, or service providers should contact that support organization for guidance and assistance with the appropriate course of action in regards to this advisory. The effectiveness of any workaround or fix is dependent on specific customer situations, such as product mix, network topology, traffic behavior, and organizational mission. Due to the variety of affected products and releases, customers should consult with their service provider or support organization to ensure any applied workaround or fix is the most appropriate for use in the intended network before it is deployed. Customers without Service Contracts +---------------------------------- Customers who purchase direct from Cisco but do not hold a Cisco service contract, and customers who purchase through third-party vendors but are unsuccessful in obtaining fixed software through their point of sale should acquire upgrades by contacting the Cisco Technical Assistance Center (TAC). TAC contacts are as follows. * +1 800 553 2447 (toll free from within North America) * +1 408 526 7209 (toll call from anywhere in the world) * e-mail: tac(a)cisco.com Customers should have their product serial number available and be prepared to give the URL of this notice as evidence of entitlement to a free upgrade. Free upgrades for non-contract customers must be requested through the TAC. Refer to: http://www.cisco.com/en/US/support/tsd_cisco_worldwide_contacts.html for additional TAC contact information, including localized telephone numbers, and instructions and e-mail addresses for use in various languages. Exploitation and Public Announcements ===================================== The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerability described in this advisory. This vulnerability was discovered during internal testing. Status of this Notice: FINAL ============================ THIS DOCUMENT IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF THE INFORMATION ON THE DOCUMENT OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME. A stand-alone copy or Paraphrase of the text of this document that omits the distribution URL in the following section is an uncontrolled copy, and may lack important information or contain factual errors. Distribution ============ This advisory is posted on Cisco's worldwide website at: http://www.cisco.com/warp/public/707/cisco-sa-20090923-sip.shtml In addition to worldwide web posting, a text version of this notice is clear-signed with the Cisco PSIRT PGP key and is posted to the following e-mail and Usenet news recipients. * cust-security-announce(a)cisco.com * first-bulletins(a)lists.first.org * bugtraq(a)securityfocus.com * vulnwatch(a)vulnwatch.org * cisco(a)spot.colorado.edu * cisco-nsp(a)puck.nether.net * full-disclosure(a)lists.grok.org.uk * comp.dcom.sys.cisco(a)newsgate.cisco.com Future updates of this advisory, if any, will be placed on Cisco's worldwide website, but may or may not be actively announced on mailing lists or newsgroups. Users concerned about this problem are encouraged to check the above URL for any updates. Revision History ================ +----------------------------------------+ | Revision | | Initial | | 1.0 | 2009-September-23 | public | | | | release | +----------------------------------------+ Cisco Security Procedures ========================= Complete information on reporting security vulnerabilities in Cisco products, obtaining assistance with security incidents, and registering to receive security information from Cisco, is available on Cisco's worldwide website at: http://www.cisco.com/en/US/products/products_security_vulnerability_policy.… This includes instructions for press inquiries regarding Cisco security notices. All Cisco security advisories are available at: http://www.cisco.com/go/psirt -----BEGIN PGP SIGNATURE----- iD8DBQFKukGZ86n/Gc8U/uARAh54AJ4jQJCLVMauxJXj00WMu822+kH1TQCfTzA6 2++Xtx6BvyycWfoy75Zjtx0= =nUyE -----END PGP SIGNATURE-----

1 0

Cisco Security Advisory: Cisco IOS Software Crafted Encryption Packet Denial of Service Vulnerability
by Cisco Systems Product Security Incident Response Team 23 Sep '09

23 Sep '09

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Cisco Security Advisory: Cisco IOS Software Crafted Encryption Packet Denial of Service Vulnerability Advisory ID: cisco-sa-20090923-tls Revision 1.0 For Public Release 2009 September 23 +--------------------------------------------------------------------- Summary ======= Cisco IOS� Software contains a vulnerability that could allow an attacker to cause a Cisco IOS device to reload by remotely sending a crafted encryption packet. Cisco has released free software updates that address this vulnerability. This advisory is posted at: http://www.cisco.com/warp/public/707/cisco-sa-20090923-tls.shtml Note: The September 23, 2009, Cisco IOS Security Advisory bundled publication includes eleven Security Advisories. Ten of the advisories address vulnerabilities in Cisco IOS Software, and one advisory addresses a vulnerability in Cisco Unified Communications Manager. Each advisory lists the releases that correct the vulnerability or vulnerabilities detailed in the advisory. The following table lists releases that correct all Cisco IOS Software vulnerabilities that have been published on September 23, 2009, or earlier. http://www.cisco.com/warp/public/707/cisco-sa-20090923-bundle.shtml Individual publication links are in "Cisco Event Response: Semiannual Cisco IOS Software Advisory Bundled Publication" at the following link: http://www.cisco.com/web/about/security/intelligence/Cisco_ERP_sep09.html Affected Products ================= Vulnerable Products +------------------ Devices running affected versions of Cisco IOS Software are susceptible if configured with any of the following features: * Secure Socket Layer (SSL) Virtual Private Network (VPN) * Secure Shell (SSH) * Internet Key Exchange (IKE) Encrypted Nonces Note: Other SSL/HTTPS related features than WebVPN and SSL VPN are not affected by this vulnerability. To determine whether SSLVPN is enabled on a device, log in to the device and issue the command-line interface (CLI) command "show running-config | include webvpn". If the device returns any output then SSLVPN is configured and the device may be vulnerable. Vulnerable configurations vary depending on whether the device is supporting Cisco IOS WebVPN (introduced in Release 12.3(14)T) or Cisco IOS SSLVPNs (introduced in Release 12.4(6)T). The following methods describe how to confirm if the device is vulnerable: If the output from "show running-config | include webvpn" contains "webvpn enable" then the device is configured with the original Cisco IOS WebVPN. The only way to determine whether the device is vulnerable is to examine the output of "show running-config" to confirm that webvpn is enabled via the command "webvpn enable" and that a "ssl trustpoint" has been configured. The following example shows a vulnerable device configured with Cisco IOS WebVPN: webvpn enable ! webvpn ssl trustpoint TP-self-signed-29742012 If the output from "show running-config | include webvpn" contains "webvpn gateway <word>" then the device is supporting the Cisco IOS SSLVPN feature. A device is vulnerable if it has the "inservice" command in at least one of the "webvpn gateway" sections. The following example shows a vulnerable device configured with Cisco IOS SSLVPN: Router# show running | section webvpn webvpn gateway Gateway ip address 10.1.1.1 port 443 ssl trustpoint Gateway-TP inservice ! Router# A device that supports the Cisco IOS SSLVPN is not vulnerable if it has no "webvpn gateways" configured or all the configured "webvpn gateways" contain the "no inservice" webvpn gateway command. To determine if SSH is enabled use the "show ip ssh" command, as shown in the following example: Router#show ip ssh SSH Enabled - version 1.99 Authentication timeout: 120 secs; Authentication retries: 3 Minimum expected Diffie Hellman key size : 1024 bits To determine if the IKE encrypted nonces feature is enabled, use the "show running-config | include rsa-encr" command as follows: Router#show running-config | inc rsa-encr authentication rsa-encr To determine the Cisco IOS Software release that is running on a Cisco product, administrators can log in to the device and issue the show version command to display the system banner. The system banner confirms that the device is running Cisco IOS Software by displaying text similar to "Cisco Internetwork Operating System Software" or "Cisco IOS Software." The image name displays in parentheses, followed by "Version" and the Cisco IOS Software release name. Other Cisco devices do not have the show version command or may provide different output. The following example identifies a Cisco product that is running Cisco IOS Software Release 12.3(26) with an installed image name of C2500-IS-L: Router#show version Cisco Internetwork Operating System Software IOS (tm) 2500 Software (C2500-IS-L), Version 12.3(26), RELEASE SOFTWARE (fc2) Technical Support: http://www.cisco.com/techsupport Copyright (c) 1986-2008 by cisco Systems, Inc. Compiled Mon 17-Mar-08 14:39 by dchih !--- output truncated The following example identifies a Cisco product that is running Cisco IOS Software Release 12.4(20)T with an installed image name of C1841-ADVENTERPRISEK9-M: Router#show version Cisco IOS Software, 1841 Software (C1841-ADVENTERPRISEK9-M), Version 12.4(20)T, RELEASE SOFTWARE (fc3) Technical Support: http://www.cisco.com/techsupport Copyright (c) 1986-2008 by Cisco Systems, Inc. Compiled Thu 10-Jul-08 20:25 by prod_rel_team !--- output truncated Additional information about Cisco IOS Software release naming conventions is available in "White Paper: Cisco IOS Reference Guide" at the following link: http://www.cisco.com/warp/public/620/1.html Products Confirmed Not Vulnerable +-------------------------------- The Cisco ASA 5500 Series Adaptive Security Appliances are not affected by this vulnerability. Cisco IOS XR Software is not affected by this vulnerability. No other Cisco products are currently known to be affected by this vulnerability. Details ======= A Cisco IOS device that is configured for SSLVPN or SSH may reload when it receives a specially crafted TCP packet on TCP port 443 (SSLVPN) or TCP port 22 (SSH). Completion of the three-way handshake to the associated TCP port number of these features is required for the vulnerability to be successfully exploited; however, authentication is not required. A Cisco IOS device that is configured for IKE encrypted nonces may reload when it receives a specially crafted UDP packet on port 500 or 4500 (if configured for NAT Traversal (NAT-T)). This vulnerability is documented in Cisco bug ID CSCsq24002 and has been assigned the Common Vulnerabilities and Exposures (CVE) identifier CVE-2009-2871. Vulnerability Scoring Details ============================= Cisco has provided scores for the vulnerability in this advisory based on the Common Vulnerability Scoring System (CVSS). The CVSS scoring in this Security Advisory is done in accordance with CVSS version 2.0. CVSS is a standards-based scoring method that conveys vulnerability severity and helps determine urgency and priority of response. Cisco has provided a base and temporal score. Customers can then compute environmental scores to assist in determining the impact of the vulnerability in individual networks. Cisco has provided an FAQ to answer additional questions regarding CVSS at: http://www.cisco.com/web/about/security/intelligence/cvss-qandas.html Cisco has also provided a CVSS calculator to help compute the environmental impact for individual networks at: http://intellishield.cisco.com/security/alertmanager/cvss CSCsq24002 - Crafted Encrypted packet may cause device reload CVSS Base Score - 7.8 Access Vector - Network Access Complexity - Low Authentication - None Confidentiality Impact - None Integrity Impact - None Availability Impact - Complete CVSS Temporal Score - 6.4 Exploitability - Functional Remediation Level - Official-Fix Report Confidence - Confirmed Impact ====== Successful exploitation of the vulnerability described in this document may result in a reload of the device. The issue could be repeatedly exploited to cause an extended DoS condition. Software Versions and Fixes =========================== When considering software upgrades, also consult: http://www.cisco.com/go/psirt and any subsequent advisories to determine exposure and a complete upgrade solution. In all cases, customers should exercise caution to be certain the devices to be upgraded contain sufficient memory and that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, contact the Cisco Technical Assistance Center (TAC) or your contracted maintenance provider for assistance. Each row of the Cisco IOS software table (below) names a Cisco IOS release train. If a given release train is vulnerable, then the earliest possible releases that contain the fix (along with the anticipated date of availability for each, if applicable) are listed in the "First Fixed Release" column of the table. The "Recommended Release" column indicates the releases which have fixes for all the published vulnerabilities at the time of this Advisory. A device running a release in the given train that is earlier than the release in a specific column (less than the First Fixed Release) is known to be vulnerable. Cisco recommends upgrading to a release equal to or later than the release in the "Recommended Releases" column of the table. +-------------------------------------------------------------------+ | Major | Availability of Repaired Releases | | Release | | |------------+------------------------------------------------------| | Affected | | Recommended | | 12.0-Based | First Fixed Release | Release | | Releases | | | |-------------------------------------------------------------------| | There are no affected 12.0 based releases. | |-------------------------------------------------------------------| | Affected | | Recommended | | 12.1-Based | First Fixed Release | Release | | Releases | | | |-------------------------------------------------------------------| | There are no affected 12.1 based releases. | |-------------------------------------------------------------------| | Affected | | Recommended | | 12.2-Based | First Fixed Release | Release | | Releases | | | |------------+----------------------------------------+-------------| | 12.2 | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2B | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2BC | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2BW | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2BX | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2BY | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2BZ | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2CX | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2CY | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2CZ | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2DA | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2DD | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2DX | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2EW | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2EWA | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2EX | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2EY | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2EZ | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2FX | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2FY | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2FZ | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2IRA | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2IRB | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2IRC | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2IXA | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2IXB | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2IXC | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2IXD | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2IXE | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2IXF | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2IXG | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2IXH | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2JA | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2JK | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2MB | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2MC | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2S | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SB | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SBC | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SCA | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SCB | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SE | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SEA | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SEB | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SEC | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SED | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SEE | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SEF | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SEG | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SG | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SGA | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SL | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SM | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SO | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SQ | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SRA | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SRB | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SRC | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SRD | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2STE | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SU | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SV | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SVA | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SVC | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SVD | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SVE | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SW | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SX | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SXA | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SXB | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SXD | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SXE | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SXF | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SXH | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SXI | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SY | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2SZ | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2T | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2TPC | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XA | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XB | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XC | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XD | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XE | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XF | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XG | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XH | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XI | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XJ | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XK | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XL | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XM | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XNA | Please see Cisco IOS-XE Software | | | | Availability | | |------------+----------------------------------------+-------------| | 12.2XNB | Please see Cisco IOS-XE Software | | | | Availability | | |------------+----------------------------------------+-------------| | 12.2XNC | Please see Cisco IOS-XE Software | | | | Availability | | |------------+----------------------------------------+-------------| | 12.2XND | Please see Cisco IOS-XE Software | | | | Availability | | |------------+----------------------------------------+-------------| | 12.2XO | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XQ | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XR | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XS | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XT | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XU | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XV | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2XW | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YA | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YB | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YC | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YD | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YE | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YF | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YG | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YH | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YJ | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YK | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YL | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YM | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YN | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YO | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YP | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YQ | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YR | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YS | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YT | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YU | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YV | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YW | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YX | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YY | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2YZ | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2ZA | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2ZB | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2ZC | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2ZD | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2ZE | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2ZF | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2ZG | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2ZH | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2ZJ | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2ZL | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2ZP | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2ZU | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2ZX | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2ZY | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.2ZYA | Not Vulnerable | | |------------+----------------------------------------+-------------| | Affected | | Recommended | | 12.3-Based | First Fixed Release | Release | | Releases | | | |-------------------------------------------------------------------| | There are no affected 12.3 based releases. | |-------------------------------------------------------------------| | Affected | | Recommended | | 12.4-Based | First Fixed Release | Release | | Releases | | | |------------+----------------------------------------+-------------| | 12.4 | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4GC | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4JA | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4JDA | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4JDC | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4JDD | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4JK | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4JL | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4JMA | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4JMB | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4JX | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4MD | 12.4(15)MD3 | 12.4(15)MD3 | |------------+----------------------------------------+-------------| | 12.4MDA | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4MR | 12.4(19)MR3 | 12.4(19)MR3 | |------------+----------------------------------------+-------------| | | | 12.4(15)T10 | | 12.4SW | Vulnerable; first fixed in 12.4T | | | | | 12.4(20)T4 | |------------+----------------------------------------+-------------| | | 12.4(22)T2 | | | | | 12.4(15)T10 | | 12.4T | 12.4(20)T3 | | | | | 12.4(20)T4 | | | 12.4(24)T | | |------------+----------------------------------------+-------------| | 12.4XA | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4XB | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4XC | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4XD | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4XE | Not Vulnerable | | |------------+----------------------------------------+-------------| | | | 12.4(15)T10 | | 12.4XF | Vulnerable; first fixed in 12.4T | | | | | 12.4(20)T4 | |------------+----------------------------------------+-------------| | 12.4XG | Not Vulnerable | | |------------+----------------------------------------+-------------| | | | 12.4(15)T10 | | 12.4XJ | Vulnerable; first fixed in 12.4T | | | | | 12.4(20)T4 | |------------+----------------------------------------+-------------| | | | 12.4(15)T10 | | 12.4XK | Vulnerable; first fixed in 12.4T | | | | | 12.4(20)T4 | |------------+----------------------------------------+-------------| | 12.4XL | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4XM | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4XN | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4XP | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4XQ | 12.4(15)XQ3 | 12.4(15)T10 | |------------+----------------------------------------+-------------| | | | 12.4(15)XR7 | | 12.4XR | 12.4(15)XR5 | | | | | 12.4(22)XR | |------------+----------------------------------------+-------------| | 12.4XT | Not Vulnerable | | |------------+----------------------------------------+-------------| | | Vulnerable; Contact your support | | | 12.4XV | organization per the instructions in | | | | Obtaining Fixed Software section of | | | | this advisory | | |------------+----------------------------------------+-------------| | | | 12.4(15)T10 | | 12.4XW | Vulnerable; first fixed in 12.4T | | | | | 12.4(20)T4 | |------------+----------------------------------------+-------------| | | | 12.4(15)T10 | | 12.4XY | Vulnerable; first fixed in 12.4T | | | | | 12.4(20)T4 | |------------+----------------------------------------+-------------| | | | 12.4(15)T10 | | 12.4XZ | Vulnerable; first fixed in 12.4T | | | | | 12.4(20)T4 | |------------+----------------------------------------+-------------| | | | 12.4(15)T10 | | 12.4YA | Vulnerable; first fixed in 12.4T | | | | | 12.4(20)T4 | |------------+----------------------------------------+-------------| | 12.4YB | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4YD | Not Vulnerable | | |------------+----------------------------------------+-------------| | 12.4YE | Not Vulnerable | | +-------------------------------------------------------------------+ Note: No Cisco IOS Software Modularity releases are affected by this vulnerability. Cisco IOS XE Software +-------------------------------------------------------------------+ | IOS XE Release | First Fixed Release | |----------------------------+--------------------------------------| | 2.1.x | Not Vulnerable | |----------------------------+--------------------------------------| | 2.2.x | Not Vulnerable | |----------------------------+--------------------------------------| | 2.3.x | 2.3.2 | |----------------------------+--------------------------------------| | 2.4.x | Not Vulnerable | +-------------------------------------------------------------------+ Workarounds =========== There are no available workarounds other than disabling the affected features and protecting SSH access with the use of VTY access control lists. Use the "no webvpn enable" command to disable SSL VPN use. For Cisco IOS the SSH server can be disabled by applying the command "crypto key zeroize rsa" while in configuration mode. The SSH server is enabled automatically upon generating an RSA key pair. Zeroing the RSA keys is the only way to completely disable the SSH server. Access to the SSH server on Cisco IOS Software may also be disabled by removing SSH as a valid transport protocol. This action can be done by reapplying the transport input command with 'ssh' removed from the list of permitted transports on vty lines while in configuration mode. For example: line vty 0 4 transport input telnet end If SSH server functionality is desired, access to the server can be restricted to specific source IP addresses or blocked entirely through the use of Access Control Lists (ACLs) on the vty lines as shown in the following URL: http://www.cisco.com/en/US/docs/switches/lan/catalyst2950/software/release/… More information on configuring ACLs can be found on Cisco's public website: http://www.cisco.com/en/US/products/sw/secursw/ps1018/products_tech_note091… The following is an example of a vty access-list: access-list 2 permit 10.1.1.0 0.0.0.255 access-list 2 deny any line vty 0 4 access-class 2 in In the previous example, only the 10.1.1.0/24 network is allowed to SSH to the Cisco IOS device. To disable IKE encrypted nonces use the "no authentication rsa-encr" command under an ISAKMP policy, as shown in the following example: crypto isakmp policy no authentication rsa-encr Obtaining Fixed Software ======================== Cisco has released free software updates that address these vulnerabilities. Prior to deploying software, customers should consult their maintenance provider or check the software for feature set compatibility and known issues specific to their environment. Customers may only install and expect support for the feature sets they have purchased. By installing, downloading, accessing or otherwise using such software upgrades, customers agree to be bound by the terms of Cisco's software license terms found at: http://www.cisco.com/en/US/docs/general/warranty/English/EU1KEN_.html or as otherwise set forth at Cisco.com Downloads at: http://www.cisco.com/public/sw-center/sw-usingswc.shtml Do not contact psirt(a)cisco.com or security-alert(a)cisco.com for software upgrades. Customers with Service Contracts +------------------------------- Customers with contracts should obtain upgraded software through their regular update channels. For most customers, this means that upgrades should be obtained through the Software Center on Cisco's worldwide website at http://www.cisco.com. Customers using Third Party Support Organizations +------------------------------------------------ Customers whose Cisco products are provided or maintained through prior or existing agreements with third-party support organizations, such as Cisco Partners, authorized resellers, or service providers should contact that support organization for guidance and assistance with the appropriate course of action in regards to this advisory. The effectiveness of any workaround or fix is dependent on specific customer situations, such as product mix, network topology, traffic behavior, and organizational mission. Due to the variety of affected products and releases, customers should consult with their service provider or support organization to ensure any applied workaround or fix is the most appropriate for use in the intended network before it is deployed. Customers without Service Contracts +---------------------------------- Customers who purchase direct from Cisco but do not hold a Cisco service contract, and customers who purchase through third-party vendors but are unsuccessful in obtaining fixed software through their point of sale should acquire upgrades by contacting the Cisco Technical Assistance Center (TAC). TAC contacts are as follows. * +1 800 553 2447 (toll free from within North America) * +1 408 526 7209 (toll call from anywhere in the world) * e-mail: tac(a)cisco.com Customers should have their product serial number available and be prepared to give the URL of this notice as evidence of entitlement to a free upgrade. Free upgrades for non-contract customers must be requested through the TAC. Refer to: http://www.cisco.com/en/US/support/tsd_cisco_worldwide_contacts.html for additional TAC contact information, including localized telephone numbers, and instructions and e-mail addresses for use in various languages. Exploitation and Public Announcements ===================================== The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerability described in this advisory. This vulnerability was found during internal testing. Status of this Notice: FINAL ============================ THIS DOCUMENT IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF THE INFORMATION ON THE DOCUMENT OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME. A stand-alone copy or Paraphrase of the text of this document that omits the distribution URL in the following section is an uncontrolled copy, and may lack important information or contain factual errors. Distribution ============ This advisory is posted on Cisco's worldwide website at: http://www.cisco.com/warp/public/707/cisco-sa-20090923-tls.shtml In addition to worldwide web posting, a text version of this notice is clear-signed with the Cisco PSIRT PGP key and is posted to the following e-mail and Usenet news recipients. * cust-security-announce(a)cisco.com * first-bulletins(a)lists.first.org * bugtraq(a)securityfocus.com * vulnwatch(a)vulnwatch.org * cisco(a)spot.colorado.edu * cisco-nsp(a)puck.nether.net * full-disclosure(a)lists.grok.org.uk * comp.dcom.sys.cisco(a)newsgate.cisco.com Future updates of this advisory, if any, will be placed on Cisco's worldwide website, but may or may not be actively announced on mailing lists or newsgroups. Users concerned about this problem are encouraged to check the above URL for any updates. Revision History ================ +----------------------------------------+ | Revision | | Initial | | 1.0 | 2009-September-23 | public | | | | release | +----------------------------------------+ Cisco Security Procedures ========================= Complete information on reporting security vulnerabilities in Cisco products, obtaining assistance with security incidents, and registering to receive security information from Cisco, is available on Cisco's worldwide website at: http://www.cisco.com/en/US/products/products_security_vulnerability_policy.… This includes instructions for press inquiries regarding Cisco security notices. All Cisco security advisories are available at: http://www.cisco.com/go/psirt -----BEGIN PGP SIGNATURE----- iD8DBQFKukGd86n/Gc8U/uARAltxAJsHsWKROOB5Ph8mcFs+ZUIYygRoEgCePeZX A9ezksakGzQynAYZbBjJ+uE= =n8Uh -----END PGP SIGNATURE-----

1 0

Wireless STM-1 link
by Rens 23 Sep '09

23 Sep '09

Hi all, I'm encountering a problem with a wireless STM-1 link which has a switch connected at each end. The wireless link has Gigabit Ethernet interfaces and so have my switches. When I ping between the 2 switches via that wireless link I'm getting a lot of pings that are lost. The wireless link is not saturated but I'm thinking it could have to do something with the gigabit interfaces and only having 155Mbps on the link itself? All ideas welcome. Regards, Rens

11 15

SAS70 Type II compliant colo providers - Chicago, IL
by Andy Ashley 23 Sep '09

23 Sep '09

Hi, I would really appreciate any recommendations for SAS70 Type II compliant colocation providers in Chicago, IL The requirement is fairly small (1/2 - 1 rack). Mail me off list please. Thanks. Regards, Andy. -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.

6 7

802.17b Case studies and current usage on Metro Ethernets
by Fabio Mendes 23 Sep '09

23 Sep '09

I'd appreciate if someone could answer some of my questions: 1. What vendors currently offer support to the IEEE 802.17b standard ? 2. After extensive searching, have found no case studies. Do you guys could recomend any ? 3. If someone had been envolved with 802.17's deployments, what are your thoughts about it ? I mean, the whole process as well as the benefits (and problems) that arose. Thanks !

2 1

Contact w/ clue re: AT&T SMS email gateway?
by Dave Pascoe 22 Sep '09

22 Sep '09

Recently something seems to have changed with the @txt.att.net email to SMS gateway. Messages sent through the gateway suffer from the following: 1) Long delay in reaching the phone (intermittent) (yes I know there is no latency guarantee) and, even more crippling, 2) Message comes through as just "SMS Message" instead of the SMTP message content. And the sender is always 410-000-01x, where x increments by 1 with each new incoming email-to-SMS gateway-handled message. Phone is an iPhone 3GS. This has worked fine for quite a while. No changes on the iPhone. I have gone through normal AT&T Wireless Customer Service but there isn't much clue there - had to explain what an email to SMS gateway is. Anyone elese seeing this? Anyone from AT&T Wireless here? Please contact me off-list. TIA, Dave Pascoe

5 6

RETRACTION : SMS
by Aaron D. Osgood 22 Sep '09

22 Sep '09

My apologies for the wasted bandwidth - my last message was not intended for the list (NOTE TO SELF: Double check the TO line when I hit REPLY!) Aaron D. Osgood Streamline Solutions L.L.C P.O. Box 6115 Falmouth, ME 04105 TEL: 207-781-5561 FAX: 615-704-8067 MOBILE: 207-831-5829 <mailto:AOsgood@Streamline-Solutions.net> AOsgood(a)Streamline-Solutions.net http://www.streamline-solutions.net Introducing Efficiency to Business since 1986.

1 0

UDP and IP fragmentation
by Philip Lavine 22 Sep '09

22 Sep '09

To all, I am running a Windows based high performance computing application that uses "reliable" multicast (29West) on a gigabit LAN. All systems are logically on the same VLAN and even on the same physical switch The application is set to use an 8k buffer and therefore results in IP fragmentation when datagrams are transmitted. The application is sensitive to any latency or data loss (of course) and uses a proprietary mechanism to create TCP-like retransmissions in case there is any actual data loss. Unfortunately, becasue of the fragmentation during the retransmission window all ip fragments must be resent even though only one may have been lost. If the buffer size is tweeked to the ~1460 this may fix the fragmentation but will the side effects be less throughput and possibly more latency. Is there a sweet spot for UDP on an ethernet segment? Philip

2 1