Cisco IOS Software Internet Key Exchange Version 1 Fragmentation Denial of Service Vulnerability (cisco-sa-20160928-ios-ikev1)

A vulnerability in the Internet Key Exchange version 1 (IKEv1) fragmentation code of Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to cause an exhaustion of available memory or a reload of the affected system.
The vulnerability is due to the improper handling of crafted, fragmented IKEv1 packets.

An attacker could exploit this vulnerability by sending crafted UDP packets to the affected system. An exploit could allow the attacker to cause a reload of the affected system.

Refer to Cisco advisory cisco-sa-20160928-ios-ikev1 for updates and patch information.

Patch:
Following are links for downloading patches to fix the vulnerabilities:

cisco-sa-20160928-ios-ikev1: CISCO IOS