Unspecified vulnerability in the Multi Protocol Label Switching (MPLS) Forwarding Infrastructure (MFI) in Cisco IOS 12.2 and 12.4 allows remote attackers to cause a denial of service (memory corruption) via crafted packets for which the software path is used.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A5619
http://www.vupen.com/english/advisories/2008/2670
http://www.cisco.com/en/US/products/products_security_advisory09186a0080a014ac.shtml