Cisco IOS Software High Priority Queue Denial of Service Vulnerability

A vulnerability in the packet driver code of Cisco IOS Software could allow an unauthenticated, remote attacker to cause a reload of the affected device, resulting in a denial of service (DoS) condition.

The vulnerability is due to how the packet driver code handles packets that belong to protocols that engage high priority queues, such as Virtual Switching Systems (VSS) or Bidirectional Forwarding Detection (BFD). An attacker could exploit this vulnerability by sending a number of BFD or VSS packets to be processed by an affected device. An exploit could allow the attacker to cause a reload of the affected device that would lead to a DoS condition.

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

To exploit this vulnerability, an attacker would need access to the same broadcast or collision domain as the targeted device. This access requirement may reduce the possibility of a successful exploit.