source: https://www.securityfocus.com/bid/21962/info

PHPKIT 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 implementation.

PHPKIT 1.6.1 R2 and prior versions are vulnerable to this issue.

http://www.example.com/comment.php&comcat=gb&subid=-1'%20UNION%20SELECT%201,1,1,1,1,1,user_pw,1%20from%20PHPKIT_USER_TABLE%20where%20%20user_id=1/*