On 7/31/13, Blake Dunlap <ikiris@gmail.com> wrote:
I bet blocking all SYN packets and non related flow UDP packets to customers would be even more effective. Why don't we do that and be done with it instead of playing whack a mole every 3 months when someone finds some new service that was poorly designed so that it can be used to send a flood?
Because it breaks applications that people are paying to be able to use. The way I see it; more and more samples keep getting found about protocols abused because networks have not implemented BCP38. The latest SNMP trend is just another uptick to the sample size, and proof that Closing off perfectly OK recursive DNS services is totally inadequate and not a useful long-term fix to the problem of DDoS or IP/UDP reflection attacks. Asking folks to improve the security of access to their SNMP instances is just chasing the latest exploit implementation, with no attention to the vulnerability or the root cause.... -- -JH