source: http://www.securityfocus.com/bid/37999/info

XAMPP is prone to a local file-include vulnerability because it fails to sufficiently sanitize user-supplied input data.

An attacker can exploit this vulnerability to obtain potentially sensitive information and execute arbitrary local scripts in the context of the webserver process. This may allow the attacker to compromise the application and the computer; other attacks are also possible.

This issue affects XAMPP 1.6.8 and prior; other versions may be vulnerable as well. 

http://www.example.com/xampp/showcode.php?showcode=1&file=../index.php