source: https://www.securityfocus.com/bid/31966/info

Elkagroup is prone to an SQL-injection vulnerability because the application fails 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.

This issue affects Elkagroup 1.0; other versions may also be affected. 

http://www.example.com/view.php?cid=-33%20UNION%20ALL%20SELECT%200,user(),0,0,0,0,0,0,0,0,0,0,0,0,0,0,0--&uid=0&new=0