The IKEv1 implementation in Cisco ASA Software 7.x, 8.0.x, 8.1.x, and 8.2.x before 8.2.2.13 allows remote authenticated users to bypass XAUTH authentication via crafted IKEv1 packets, aka Bug ID CSCus47259.
http://www.securitytracker.com/id/1032473
http://tools.cisco.com/security/center/viewAlert.x?alertId=39157