Cisco Security Advisory – A vulnerability in the DHCPv6 relay feature of Cisco Adaptive Security Appliance (ASA) software could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to insufficient validation of DHCPv6 packets. Cisco ASA Software is affected by this vulnerability only if the software is configured with the DHCPv6 relay feature. An attacker could exploit this vulnerability by sending crafted DHCPv6 packets to an affected device.