Cisco IOS Software Link Layer Discovery Protocol Denial of Service Vulnerability

A vulnerability in Link Layer Discovery Protocol (LLDP) in Cisco switches could allow an unauthenticated, adjacent attacker to cause a reload of the affected device.

The vulnerability is due to incorrect handling of malformed LLDP packets. An attacker could exploit this vulnerability by sending a malformed LLDP packet destined to a switch when LLDP is enabled on an affected device. An exploit could allow the attacker to cause a reload of the affected device.

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 collision or broadcast domain as the targeted device to send malformed LLDP packets to the device. This access requirement may reduce 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.