The IPv6 snooping functionality in the first-hop security subsystem in Cisco IOS 12.2 15.0 15.1 15.2 15.3 15.4 and 15.5 and IOS XE 3.2SE 3.3SE 3.3XO 3.4SG 3.5E and 3.6E before 3.6.3E; 3.7E before 3.7.2E; 3.9S and 3.10S before 3.10.6S; 3.11S before 3.11.4S; 3.12S and 3.13S before 3.13.3S; and 3.14S before 3.14.2S allows remote attackers to cause a denial of service (device reload) via a malformed ND packet with the Cryptographically Generated Address (CGA) option aka Bug ID CSCuo04400.