DB4Web server, when configured to use verbose debug messages, allows remote attackers to use DB4Web as a proxy and attempt TCP connections to other systems (port scan) via a request for a URL that specifies the target IP address and port, which produces a connection status in the resulting error message.
https://euvd.enisa.europa.eu/vulnerability/EUVD-2002-1467
http://www.securityfocus.com/bid/5725
http://www.iss.net/security_center/static/10136.php
http://archives.neohapsis.com/archives/vulnwatch/2002-q3/0125.html
http://archives.neohapsis.com/archives/bugtraq/2002-09/0201.html