A vulnerability in the forwarding information base (FIB) code of Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause inconsistency between the routing information base (RIB) and the FIB, resulting in a denial of service (DoS) condition. The vulnerability is due to incorrect processing of extremely long routing updates. An attacker could exploit this vulnerability by sending a large routing update. A successful exploit could allow the attacker to trigger inconsistency between the FIB and the RIB, resulting in a DoS condition. There are no workarounds that address this vulnerability. This advisory is available at the following link: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180207-iosxr
There are no workarounds that address this vulnerability.
For information about fixed software releases, consult the Cisco bug ID(s) at the top of this advisory.
When considering software upgrades, customers are advised to regularly consult the advisories for Cisco products, which are available from the Cisco Security Advisories and Alerts page, to determine exposure and a complete upgrade solution.
In all cases, customers should ensure that the devices to be upgraded contain sufficient memory and confirm that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, customers are advised to contact the Cisco Technical Assistance Center (TAC) or their contracted maintenance providers.
The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.
This vulnerability was found during the resolution of a Cisco TAC support case.
To learn about Cisco security vulnerability disclosure policies and publications, see the Security Vulnerability Policy. This document also contains instructions for obtaining fixed software and receiving security vulnerability information from Cisco.
| Version | Description | Section | Status | Date |
|---|---|---|---|---|
| 1.0 | Initial public release. | - | Final | 2018-February-07 |
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