source: http://www.securityfocus.com/bid/55205/info

PHP Web Scripts Text Exchange Pro is prone to a local file-include vulnerability because it fails to sufficiently sanitize user-supplied input.

An attacker can exploit this vulnerability to view files and execute local scripts in the context of the web server process. This may aid in further attacks. 

http://www.example.com/textexchangepro/index.php?page=../../../../../../../../../../etc/passwd%00