Cisco Security Advisory: Cisco IOS Software Session Initiation Protocol Denial of Service Vulnerability Advisory ID: cisco-sa-20131106-sip Revision 1.0 For Public Release 2013 November 6 16:00 UTC (GMT) +--------------------------------------------------------------------- Summary ======= A vulnerability exists in the Session Initiation Protocol (SIP) implementation in Cisco IOS Software that could allow an unauthenticated, remote attacker to cause a reload of an affected device or cause memory leaks that may result in system instabilities. To exploit this vulnerability, affected devices must be configured to process SIP messages. Limited Cisco IOS Software releases are affected. Cisco has released free software updates that address this vulnerability. There are no workarounds for devices that must run SIP; however, mitigations are available to limit exposure to the vulnerability. This advisory is available at the following link: http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20131106-sip