In response to feedback from operational security communities, CAIDA's source address validation measurement project (https://spoofer.caida.org) is automatically generating monthly reports of ASes originating prefixes in BGP for systems from which we received packets with a spoofed source address. We are publishing these reports to network and security operations lists in order to ensure this information reaches operational contacts in these ASes. This report summarises tests conducted within usa, can. Inferred improvements during Dec 2021: ASN Name Fixed-By 54825 PACKET 2021-12-03 Further information for the inferred remediation is available at: https://spoofer.caida.org/remedy.php Source Address Validation issues inferred during Dec 2021: ASN Name First-Spoofed Last-Spoofed 577 BACOM 2016-03-09 2021-12-29 209 CENTURYLINK-US-LEGACY-QWEST 2016-08-16 2021-12-30 20412 CLARITY-TELECOM 2016-09-30 2021-12-31 6181 FUSE-NET 2016-10-10 2021-12-27 11427 TWC-11427-TEXAS 2016-10-21 2021-12-24 32440 LONI 2016-11-03 2021-12-30 12083 WOW-INTERNET 2016-11-09 2021-12-22 1403 EBOX 2016-11-12 2021-12-08 22898 ATLINK 2016-12-16 2021-12-28 54119 BOINGO-MDU 2017-04-14 2021-12-30 701 UUNET 2017-06-14 2021-12-04 63296 AWBROADBAND 2017-09-01 2021-12-28 546 PARSONS-PGS-1 2017-11-20 2021-12-23 12222 AKAMAI 2018-02-14 2021-12-30 33452 RW 2018-09-19 2021-12-31 62904 EONIX-COMMUNICATIONS-ASBLOCK-6 2019-07-14 2021-12-29 398836 NP-NETWORKS 2021-03-12 2021-12-31 56207 Converge 2021-03-26 2021-12-01 399318 2021-08-29 2021-12-27 63457 EMPIRE-CONNECT 2021-09-08 2021-12-30 212934 AS_POTVIN 2021-10-03 2021-12-27 22773 ASN-CXA-ALL-CCI-22773-RDC 2021-10-24 2021-12-29 46449 ASTREA-NORTHWI-WESTUPMI 2021-11-07 2021-12-30 394437 PSLIGHTWAVE 2021-12-02 2021-12-27 62887 WHITESKY-COMMUNICATIONS 2021-12-03 2021-12-29 54201 WEWORK-MANAGEMENT-LLC 2021-12-16 2021-12-16 139247 2021-12-22 2021-12-22 46997 NATOLAB 2021-12-22 2021-12-29 5009 EATEL 2021-12-26 2021-12-26 4922 SHENTEL 2021-12-28 2021-12-28 Further information for these tests where we received spoofed packets is available at: https://spoofer.caida.org/recent_tests.php?country_include=usa,can&no_block=1 Please send any feedback or suggestions to spoofer-info@caida.org