Unspecified vulnerability in Cisco IOS 12.0 through 12.4 allows context-dependent attackers to cause a denial of service (device restart and BGP routing table rebuild) via certain regular expressions in a "show ip bgp regexp" command. NOTE: unauthenticated remote attacks are possible in environments with anonymous telnet and Looking Glass access.
https://puck.nether.net/pipermail/cisco-nsp/2007-August/043010.html
https://puck.nether.net/pipermail/cisco-nsp/2007-August/043002.html
http://www.vupen.com/english/advisories/2007/3136
http://www.securitytracker.com/id?1018685
http://www.securityfocus.com/bid/25352
http://www.heise-security.co.uk/news/94526/
http://www.cisco.com/en/US/products/products_security_response09186a00808bb91c.html