source: http://www.securityfocus.com/bid/14489/info

PHP-Fusion is prone to an SQL injection vulnerability.

This issue is due to a failure in the application to properly sanitize user-supplied input to the 'messages.php' script before using it in an SQL query.

Successful exploitation could result in a compromise of the application, disclosure or modification of data, or may permit an attacker to exploit vulnerabilities in the underlying database implementation. 

http://www.example.com/messages.php?msg_view='