Unspecified vulnerability in Cisco IOS 12.2 through 12.4, when the Cisco Unified Border Element feature is enabled, allows remote attackers to cause a denial of service (device reload) via crafted SIP messages, aka Bug ID CSCsx25880.
http://www.vupen.com/english/advisories/2009/2759
http://www.securitytracker.com/id?1022930
http://www.cisco.com/en/US/products/products_security_advisory09186a0080af811b.shtml
http://tools.cisco.com/security/center/viewAlert.x?alertId=18891