The Cisco IOS IP Service Level Agreement (IP SLA) feature contains a denial of service (DoS) vulnerability. The vulnerability is triggered when malformed UDP packets are sent to a vulnerable device. The vulnerable UDP port numbers depend on the device configuration. Default ports are not used for the vulnerable UDP IP SLA operation or for the UDP responder ports.
Cisco has released software updates that address this vulnerability.
This advisory is posted at http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20110928-ipsla["http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20110928-ipsla"].
Note: The September 28, 2011, Cisco IOS Software Security Advisory bundled publication includes ten Cisco Security Advisories. Nine of the advisories address vulnerabilities in Cisco IOS Software, and one advisory addresses vulnerabilities in Cisco Unified Communications Manager. Each advisory lists the Cisco IOS Software releases that correct the vulnerability or vulnerabilities detailed in the advisory as well as the Cisco IOS Software releases that correct all vulnerabilities in the September 2011 Bundled Publication.
Individual publication links are in "Cisco Event Response: Semiannual Cisco IOS Software Security Advisory Bundled Publication" at the following link: