Cisco NX-OS Software Label Distribution Protocol Message Vulnerability

A vulnerability in the Label Distribution Protocol (LDP) message processing of Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause an affected device to stop accepting valid LDP sessions during a 60-second period.

The vulnerability is due to how certain malformed LDP Hello messages are parsed. An attacker could exploit this vulnerability by sending malformed LDP Hello messages to an affected device. An exploit could allow the attacker to cause an affected device to stop accepting valid LDP sessions during a 60-second period.

Cisco has confirmed the vulnerability in a security notice; however, software updates are not available.

To exploit this vulnerability, an attacker would likely need access to trusted, internal networks to send LDP Hello messages to an affected device. This access requirement limits the possibility 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.