Cisco IOS 12.0 through 12.3YL, with BGP enabled and running the bgp log-neighbor-changes command, allows remote attackers to cause a denial of service (device reload) via a malformed BGP packet.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A5652
https://exchange.xforce.ibmcloud.com/vulnerabilities/19074
http://www.us-cert.gov/cas/techalerts/TA05-026A.html
http://www.kb.cert.org/vuls/id/689326
http://www.cisco.com/warp/public/707/cisco-sa-20050126-bgp.shtml