The remote web server contains a PHP script that is susceptible to a local file inclusion attack.
The remote host is running trixbox dashboard, a PHP-based front-end for trixbox, an IP-PBX software solution. The version of trixbox dashboard installed on the remote host fails to sanitize user-supplied input to the 'langChoice' parameter of the 'user/index.php' script before using it to include PHP code. Regardless of PHP's 'register_globals' setting, an unauthenticated attacker may be able to leverage this issue to view arbitrary files or to execute arbitrary PHP code on the remote host, subject to the privileges of the web server user ID.
No solution is known at this time.