source: https://www.securityfocus.com/bid/17079/info

Vegas Forum is prone to an SQL-injection vulnerability. This issue is due to a failure in the application to properly sanitize user-supplied input before using it in an SQL query. 

A successful exploit could allow an attacker to compromise the application, access or modify data, or exploit vulnerabilities in the underlying database implementation.

http://www.example.com/forum.php?postid=999% 20or%201