Cisco IOS XE 2.x and 3.x before 3.9.0S, 3.10 before 3.10.0S, 3.11 before 3.11.0S, 3.12 before 3.12.0S, 3.13 before 3.13.0S, 3.14 before 3.14.0S, and 3.15 before 3.15.0S allows remote attackers to cause a denial of service (device reload) via crafted IPv6 packets, aka Bug ID CSCub68073.
http://www.securitytracker.com/id/1031981
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20150325-iosxe