Cisco Carrier Routing System Small Packets Denial of Service Vulnerability

Cisco Carrier Routing System (CRS) contains a vulnerability that could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on a targeted system.

The vulnerability is due to the improper handling of malformed packets processed by the affected software. An unauthenticated, remote attacker could exploit the vulnerability by sending malformed packets to a targeted device. Processing the malformed packets could slow down the processing of legitimate traffic, resulting in a DoS condition.

Cisco has confirmed this vulnerability in a security notice and software updates are available.

To exploit this vulnerability, an attacker must be able to submit malformed packets to the targeted device, likely requiring the attacker to access trusted, internal networks. This access requirement limits 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.