Total Shop UK eCommerice Cross Site Scripting

`/------------------------------------------------------\  
| Total Shop UK eCommerce Generic Cross-Site Scripting |  
\------------------------------------------------------/  
  
  
Summary  
=======  
  
The open source version of Total Shop UK eCommerce based on CodeIgniter  
version 2.1.2 is subject to a cross-site scripting vulnerability. The value  
of a generic parameter was not sufficiently sanitised before being written  
to a block of Javascript code. An attacker could distribute a malicious URL  
that would trigger this vulnerability and potentially steal session cookies,  
redirect the user to a malicious URL or download malware onto their machine.  
  
CVE number: CVE-2012-4236  
Impact: Medium  
Vendor homepage: http://www.totalshopuk.com/  
Vendor notified: 06/08/2012  
Credit: Chris Cooper of Reaction Information Security  
(http://www.reactionis.co.uk/)  
  
This advisory is posted at:  
  
http://www.reactionpenetrationtesting.co.uk/totalshop-uk-generic-xss.html  
  
  
Affected Products  
======== ========  
  
Total Shop UK eCommerce based on CodeIgniter version 2.1.2 (open source  
version). Other versions may be affected.  
  
  
Details  
=======  
  
Generic parameters in the /application/modules/_main/views/_top.php file are  
written to a Javascript function in the page header without sanitisation.  
The entire URL, including the query string, is written (via a PHP echo  
construct) into a refresh_page() Javascript function. It was possible to  
escape the function and execute arbitrary Javascript code on the application  
pages.   
  
There is some character filtering in place, although this can be evaded by  
inserting a null (%00) character (see proof of concept).  
  
  
Impact  
======  
  
An attacker might entice users to follow a malicious URL, causing Javascript  
code to execute in their browser, potentially stealing session cookies,  
redirecting the user to a malicious URL or downloading malware onto their  
machine.  
  
  
Proof of Concept  
===== == =======  
  
Injecting the following Javascript code into a generic parameter on any  
application page will trigger the vulnerability, causing the page to return  
a Javascript alert box.  
  
%00";};alert(String.fromCharCode(120,115,115,116,101,115,116));{//  
  
---  
Example 1 Request:  
+-----------------  
  
GET /?%00";};alert(String.fromCharCode(120,115,115,116,101,115,116));{//=1  
HTTP/1.1  
Host: 192.168.0.6  
Referer: http://192.168.0.6/about  
  
  
---  
Example 1 Response:  
+------------------  
  
--- SNIP ---  
function refresh_page(){  
  
parent.location="/?%00";};alert(String.fromCharCode(120,115,115,116,101,115,  
116));{//=1";   
}  
--- SNIP ---  
  
  
Solution  
========  
  
Upgrade to Total Shop UK eCommerce 2.1.2_p1. Download link here:  
http://sourceforge.net/projects/totalshopuk/files/TSUK_eCommerce_v2.1.2_p1.z  
ip/download  
  
  
Distribution  
============  
  
In addition to posting on the website, a text version of this notice has  
been posted to the following e-mail and Usenet news recipients.  
  
* bugtraq () securityfocus com  
* full-disclosure () lists grok org uk  
  
Future updates of this advisory, if any, will be placed on the ReactionIS  
corporate website, but may or may not be actively announced on mailing lists  
or newsgroups. Users concerned about this problem are encouraged to check  
the URL below for any updates:  
  
  
http://www.reactionpenetrationtesting.co.uk/totalshop-uk-generic-xss.html  
  
============================================================================  
==  
  
Reaction Information Security   
Lombard House Business Centre,  
Suite 117,  
12-17 Upper Bridge Street,  
Canterbury, Kent, CT1 2NF  
  
Phone: +44 (0)1227 785050  
Email: research () reactionis {dot} co {dot} uk  
Web: http://www.reactionpenetrationtesting.co.uk  
`