Cisco Jabber for Windows Certificate Validation Vulnerability

A vulnerability in Cisco Jabber for Windows could allow an unauthenticated, remote attacker to gain a man-in-the-middle position.

The vulnerability is due to a failure to validate server certificates when negotiating a connection over Secure Sockets Layer (SSL). An attacker could exploit this vulnerability by intercepting and altering the connection.

Cisco has confirmed the vulnerability in a security notice and released software updates.

To exploit the vulnerability, the attacker may need access trusted, internal networks to convince a targeted user to accept a crafted certificate. This access requirement could reduce the likelihood of a successful exploit.

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