|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Software: vBulletin PHP Forum Version Vendor: Jelsoft Enterprises Ltd http://www.vbulletin.com Versions: 3.0.0 Release Candidate 4 Platforms: Unix/Windows Bug: Cross Site Scripting Vulnerabillity Risk: Low Exploitation: Remote with browser Date: 24 Jan 2004 Author: Rafel Ivgi, The-Insider e-mail: the_insider@mail.com web: http://theinsider.deep-ice.com ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1) Introduction 2) Bug 3) The Code ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ =============== 1) Introduction =============== Cross Site Scripting attacks are the most trusted evil urls when it concerns to forums, because forum messages are always long and contain many parameters. vBulletin is a very trusted forum, it is considered to be a very safe and security validated forum. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ====== 2) Bug ====== The Vulnerabillity is Cross Site Scripting. If an attacker will search the following quert from the server: OR in case you have problems: aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaOR just reffer to http:// /forum/search.php?do=process&showposts=0&query= ript>alert('X SS') XSS appears and the server allows an attacker to inject & execute scripts. In the words of securityfocus.com : ~~~~~~~~~~~~~~~~~~~~~~~~~~ If all of these circumstances are met, an attacker may be able to exploit this issue via a malicious link containing arbitrary HTML and script code as part of the hostname. When the malicious link is clicked by an unsuspecting user, the attacker-supplied HTML and script code will be executed by their web client. This will occur because the server will echo back the malicious hostname supplied in the client's request, without sufficiently escaping HTML and script code. Attacks of this nature may make it possible for attackers to manipulate web content or to steal cookie-based authentication credentials. It may be possible to take arbitrary actions as the victim user. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ =========== 3) The Code =========== http:// /forum/search.php?do=process&showposts=0&query=aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa http:// /forum/search.php?do=process&showposts=0&query= ript>alert('X SS') ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ --- Rafel Ivgi, The-Insider http://theinsider.deep-ice.com "Things that are unlikeable, are NOT impossible." --------------------------------------------------------------------------- Ethical Hacking at InfoSec Institute. Mention this ad and get $720 off any course! All of our class sizes are guaranteed to be 10 students or less. We provide Ethical Hacking, Advanced Ethical Hacking, Intrusion Prevention, and many other technical hands on courses. Visit us at http://www.infosecinstitute.com/securityfocus to get $720 off any course! ----------------------------------------------------------------------------