source: http://www.securityfocus.com/bid/22698/info

xt:Commerce is prone to a local file-include vulnerability because it fails to properly sanitize user-supplied input.

Exploiting this issue may allow an unauthorized user to view files and execute local scripts.

xt:Commerce 3.04 and prior versions are vulnerable to this issue. 

http://www.example.com/index.php?currency=EUR&manufacturers_id=1&template=../../../../../../../../etc/passwd%00