Cisco TelePresence Video Communication Server Expressway Access Vulnerability

A vulnerability in of the Cisco TelePresence Video Communication Server (VCS) Expressway could allow an authenticated, remote attacker to falsely register their Mobile and Remote Access (MRA) endpoint.

The vulnerability is due to insufficient validation of the registering phone line. An attacker could exploit this vulnerability by sending a crafted Session Initiation Protocol (SIP) message to the VCS Expressway. An exploit could allow the attacker to register their phones and impersonate legitimate users.

Cisco has confirmed the vulnerability; however, software updates are not available.

To exploit this vulnerability, an attacker must authenticate to the targeted device. This access requirement reduces the likelihood of a successful exploit.

Cisco indicates through the CVSS score that functional exploit code exists; however, the code is not known to be publicly available.