The remote host is vulnerable to multiple attack vectors.
The version of MyBB installed on the remote host is vulnerable to a number of vulnerabilities. The first vulnerability appears to be a cross-site scripting (XSS) flaw. The second vulnerability is a SQL injection flaw. An attacker exploiting the XSS vulnerability would be able to execute arbitrary code in the browser of unsuspecting MyBB users. An attacker exploiting the SQL injection flaw would be able to execute arbitrary SQL commands on the remote database server.
Upgrade to version 1.2.13 or higher.