Cisco Adaptive Security Appliance CX Context-Aware Security Denial of Service Vulnerability

A vulnerability in the data plane IP fragment handler of the Adaptive Security Appliance (ASA) CX Context-Aware Security module could allow an unauthenticated, remote attacker to cause the CX module to be unable to process further traffic, resulting in a denial of service (DoS) condition.

The vulnerability is due to improper handling of IP fragments. An attacker could exploit this vulnerability by sending crafted fragmented IP traffic across the CX module. An exploit could allow the attacker to exhaust free packet buffers in shared memory (SHM), causing the CX module to be unable to process further traffic, resulting in a DoS condition.

Cisco has not released and will not release software updates that address this vulnerability. There are no workarounds that address this vulnerability.

This advisory is available at the following link:

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170125-cas[“https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170125-cas”]