The remote web server is running a PHP application that is affected by multiple attack vectors.
The remote web server is running a version of MyBB earlier than 1.4.8. Such versions reportedly fail to properly sanitize user-supplied data to unspecified parameters in the 'Archive' and 'Attachment' features of the application. An attacker could exploit this flaw to launch cross-site scripting attacks.
Upgrade to MyBB 1.4.8 or later.