Cisco Security Advisory – A vulnerability in the implementation of Network Address Translation (NAT) functionality in Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to improper handling of malformed ICMP packets by the affected software. An attacker could exploit this vulnerability by sending crafted ICMP packets that require NAT processing by an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a denial of service (DoS) condition. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.