source: https://www.securityfocus.com/bid/21150/info

PHP Upload Tool is prone to an arbitrary file-upload vulnerability and a directory-traversal vulnerability. These issues occur because the application fails to sanitize user-supplied data.

An attacker could exploit these issues to execute code in the context of the webserver or to download sensitive information that could aid in further attacks.

Version 1.0 is vulnerable; other versions may also be affected.

http://www.example.com/upload/bin/download.php?filename=../conf/users.conf
http://www.example.com/upload/bin/download.php?filename=/etc/passwd