Cisco IOS XR Software Packet Parsing Denial of Service Vulnerability

Related Vulnerabilities: CVE-2014-3335  

A vulnerability in the packet parsing code of Cisco IOS XR Software for ASR 9000 Series Aggregation Services Routers could allow an unauthenticated, adjacent attacker to cause a lockup and eventual reload of a Network Processor (NP) chip and a line card processing traffic. The vulnerability is due to improper parsing of a specific packet when NetFlow sampling is configured. An attacker could exploit this vulnerability by sending a specific packet with a multicast destination MAC address through an affected device that has NetFlow sampling configured. An exploit could allow the attacker to cause a lockup and eventual reload of an NP chip and a line card processing traffic. Cisco has confirmed the vulnerability in a security notice and released software updates. To exploit this vulnerability, an attacker must have access to the same broadcast or collision domain of the targeted device. In addition, an attacker may need to acquire additional knowledge of the targeted device prior to attempting an exploit such as whether or not NetFlow sampling is configured. These requirements could decrease 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.