Cisco Expressway Series and TelePresence VCS Denial of Service Vulnerability

A vulnerability in the received packet parser of Cisco Expressway Series and Cisco TelePresence Video Communication Server (VCS) software could allow an unauthenticated, remote attacker to cause a reload of the affected system, resulting in a denial of service (DoS) condition.

The vulnerability is due to insufficient size validation of user-supplied data. An attacker could exploit this vulnerability by sending crafted H.224 data in Real-Time Transport Protocol (RTP) packets in an H.323 call. An exploit could allow the attacker to overflow a buffer in a cache that belongs to the received packet parser, which will result in a crash of the application, resulting in a DoS condition.

Cisco has released 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-expressway[“https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170125-expressway”]