Cisco IOS XR Software Slow Path Forwarding Denial of Service Vulnerability

A vulnerability in the egress packet processing function of Cisco IOS XR Software for Cisco ASR 9000 Series Aggregation Services Routers and Cisco Network Convergence System (NCS) 5000 Series Routers could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.

The vulnerability is due to improper resource allocation when an affected device processes network traffic in software switching mode. An attacker could exploit this vulnerability by sending specific streams of Layer 2 or Layer 3 protocol data units (PDUs) to an affected device. A successful exploit could cause the affected device to run out of buffer resources, which could make the device unable to process or forward traffic, resulting in a DoS condition. The device would need to be restarted to regain functionality.

Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-xr-cp-dos-ej8VB9QY [“https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-xr-cp-dos-ej8VB9QY”]