HTB22834: Path disclosure in FlatnuX

Vulnerability ID: HTB22834
Reference: http://www.htbridge.ch/advisory/path_disclosure_in_flatnux.html
Product: FlatNux
Vendor: Alessandro Vernassa ( http://www.flatnux.altervista.org/ )
Vulnerable Version: flatnux-2011-01.26 and probably prior versions
Vendor Notification: 03 February 2011
Vulnerability Type: Path disclosure
Risk level: Low
Credit: High-Tech Bridge SA - Ethical Hacking & Penetration Testing (http://www.htbridge.ch/)

Vulnerability Details:
The vulnerability exists due to failure in the "config.php", "include/functions_php.php", "sections/05_Gallery/section.php", "include/extra/fck3/filemanager.php" scripts, it's possible to generate an error that will reveal the full path of the script.
A remote user can determine the full path to the web root directory and other potentially sensitive information.
The following PoC is available:

http://host/config.php
http://host/include/functions_php.php
http://host/gallery.html?dir=./test
http://host/include/extra/fck3/filemanager.php