The remote host is vulnerable to a SQL Injection attack.
The remote host is running Moodle, an open-source content-management system written in PHP. This version of Moodle is vulnerable to a SQL Injection flaw. An attacker exploiting this flaw would send a malformed request to one of the affected PHP scripts. Successful exploitation would result in the attacker executing arbitrary commands against the backend SQL server. This would lead to a loss of confidential material, possible loss of database integrity, and possible loss of availability.
Upgrade to version 1.5.3 or higher.