Rule:--Sid:2114--Summary:This event is generated when a remote attacker attempts to send a large number of null characters to port 512 on an internal server. This may indicate an attempt to exploit a buffer overflow condition in Pragma Systems TelnetServer 2000.--Impact:Denial of service by anonymous, remote users.--Detailed Information:Pragma Systems TelnetServer 2000 contains a vulnerability where a large number of null characters sent to the Telnet server's rexec port can crash the server. --Affected Systems:Pragma Systems TelnetServer 2000--Attack Scenarios:A remote attacker can send messages that contain a large number of null characters to the Telnet server, causing the server to crash.--Ease of Attack:Simple. An exploit exists.--False Positives:None known.--False Negatives:None known.--Corrective Action:Upgrade to TelnetServer 2000 build 2 or higher.--Contributors:Sourcefire Research TeamBrian Caswell <bmc@sourcefire.com>Sourcefire Technical Publications TeamJen Harvey <jennifer.harvey@sourcefire.com>--Additional References:Bugtraqhttp://www.securityfocus.com/bid/1605CVEhttp://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2000-0708--