I was poking around my own server because I had an installation of torrential and found this vuln. The problem lies in getdox.php. It works by taking an argument after a "/". This specifies a file. The DOX folder that it grabs the files from is located int /dox such that / is the directory that the main index is in. Now, you can give it the parameter of /(any file) and it will fetch that file.
EXAMPLES: http://www.example.com/torrential/dox/getdox.php/../forums.php (goes to the forums page) http://www.example.com/torrential/dox/getdox.php/../../index.html (goes to http://www.example.com/index.html in this case)
The vulnerability lies in the fact that getdox.php directly reads the file with fopen/fread.