The server IKEv1 implementation in Cisco IOS 12.2 through 12.4 and 15.0 through 15.6, IOS XE through 3.18S, IOS XR 4.3.x and 5.0.x through 5.2.x, and PIX before 7.0 allows remote attackers to obtain sensitive information from device memory via a Security Association (SA) negotiation request, aka Bug IDs CSCvb29204 and CSCvb36055 or BENIGNCERTAIN.
http://www.securitytracker.com/id/1036841
http://www.securityfocus.com/bid/93003
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160916-ikev1