Cisco has released a security advisory for a vulnerability affecting IOS XR Software for ASR 9000 Series Routers. A remote attacker could exploit this vulnerability to cause a denial-of-service condition. For updates addressing lower severity vulnerabilities, see the Cisco Security Advisories page. 
CISA encourages users and administrators to review the following advisory and apply the necessary updates. 

  • Cisco IOS XR Software for ASR 9000 Series Routers Bidirectional Forwarding Detection Denial of Service Vulnerability cisco-sa-bfd-XmRescbT

Cisco reserves the right to publish an individual Security Advisory for Cisco IOS and IOS XE Software, Cisco IOS XR Software, Cisco NX-OS Software, or Cisco ASA, FTD, and FMC Software or other products outside the published schedule. Conditions under which an out-of-cycle publication may occur include, but are not limited to, the following:

  • Cisco detects heightened public awareness of a serious vulnerability.
  • Cisco learns of active exploitation of a vulnerability.
  • Cisco works with a third-party coordination center to publicly disclose a vulnerability.