The remote host is vulnerable to an flaw that allows attackers to execute arbitrary commands.
The remote host is running FlatNuke, an open-source content management system. The remote version of this software is prone to a file upload vulnerability. An attacker can specify any arbitrary 'include' file which will then be executed on the target FlatNuke system. Successful exploitation leads to the execution of arbitrary code.
Upgrade to version 2.5.7 or higher.