CVE-2021-1501 Cisco Adaptive Security Appliance Software and Cisco Firepower Threat Defense Software SIP Denial of Service Vulnerability

A vulnerability in the SIP inspection engine of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a crash and reload of an affected device, resulting in a denial of service (DoS) condition.The vulnerability is due to a crash that occurs during a hash lookup for a SIP pinhole connection. An attacker could exploit this vulnerability by sending crafted SIP traffic through an affected device. A successful exploit could allow the attacker to cause a crash and reload of the affected device.