source: https://www.securityfocus.com/bid/28446/info
The PJIRC module for phpBB is prone to a local file-include vulnerability because it fails to properly sanitize user-supplied input.
An attacker can exploit this vulnerability using directory-traversal strings to view files and execute local scripts in the context of the webserver process. This may aid in further attacks.
http://www.example.com/forum/irc/irc.php?phpEx=./../../../../../../etc/passwd