source: https://www.securityfocus.com/bid/59886/info

The wp-FileManager plugin for WordPress is prone to a vulnerability that lets attackers download arbitrary files because the application fails to sufficiently sanitize user-supplied input.

An attacker can exploit this issue to download arbitrary files within the context of the web server process. Information obtained may aid in further attacks.

http://www.example.com/wp-content/plugins/wp-filemanager/incl/libfile.php?&path=../../&filename=wp-config.php&action=download