CVE-2002-0964
Half-Life Server 1.1.1.0 and earlier allows remote attackers to cause a denial of service (resource exhaustion) via multiple responses to the initial challenge with different cd_key values, which reaches the player limit and prevents other players from connecting until the original responses have timed out.
Date published : 2003-04-02
http://www.securityfocus.com/bid/5076
http://archives.neohapsis.com/archives/bugtraq/2002-06/0248.html
