source: https://www.securityfocus.com/bid/20292/info

DeluxeBB is prone to a remote file-include vulnerability because the application fails to properly sanitize user-supplied input.

An attacker can exploit this issue to include arbitrary remote files containing malicious PHP code and execute it in the context of the webserver process. This may allow the attacker to compromise the application and the underlying system; other attacks are also possible.

This issue affects version 1.09; other versions may also be vulnerable.

http://www.example.com/templates/deluxe/cp/sig.php?settings[smilies]=on&templatefolder=[file]%00