Seeker Advisory Sep11: Reflected Cross Site Scripting in Microsoft SharePoint Portal

["Irene Abezgauz" <irene@xxxxxxxxxxxxx>]

Seeker Research Center Security Advisory 

This vulnerability was discovered by Seeker® Automatic Run-Time Application 
Security Testing Solution 
Disclosed By Irene Abezgauz, September 13th, 2011

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I. Overview
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A Cross Site Scripting vulnerability has been identified in Microsoft 
SharePoint 2007. This vulnerability allows attackers to gain control over valid 
user accounts, perform operations on their behalf, redirect them to malicious 
sites, steal their credentials, and more.

A friendly formatted version of this advisory is available at: 
http://www.seekersec.com/Advisories/SeekerAdvMS04.html 

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II. Details
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The Contact Details Tool Pane web part is vulnerable to cross site scripting 
attacks in the parameter 
ctl00$MSOTlPn_EditorZone$Edit0g_7aaa0c6d_72f5_4717_9b22_80188ffdbcde$peopleEditor$hiddenSpanData=
By manipulating an unsuspecting user into submitting a specially crafted form 
an attacker causes the victim to send the malicious script to the vulnerable 
SharePoint 2007 instance. The malicious script is then reflected back to the 
user and executed on his browser. 
The Contact Details Tool Pane is an out-of-the-box component, accessible from 
various locations in SharePoint 2007 in which the Contact Details web-part is 
present. The exploit in this advisory has been produced when editing Report 
Center.

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III. Exploit 
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Sample exploitation of this vulnerability would be crafting the following 
request:  
POST /Reports/Pages/Default.aspx HTTP/1.1
…
ctl00$MSOTlPn_EditorZone$Edit0g_7aaa0c6d_72f5_4717_9b22_80188ffdbcde$peopleEditor$hiddenSpanData=<script>alert(“SeekerSec”)</script>

The request also contains other parameters required by the page, the vulnerable 
parameter being the parameter noted above. 
It seems that when a script is simply placed into the input field there is a 
client-side encoding of the parameter value, which is insufficient to prevent 
attacks as directly (not via client) submitted scripts simply do not undergo 
such validation. 

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IV. Affected Systems
================
Microsoft SharePoint 2007

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V. Solution
========
Microsoft has released a fix for this vulnerability, see 
http://technet.microsoft.com/security/bulletin/MS11-074 for further 
information. 

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VI. Credit
=======
The vulnerability was automatically discovered by Seeker® - New generation 
application security testing solution, utilizing ground breaking BRITE™ 
technology (Behavioral Runtime Intelligent Testing Engine).

Further research and publication was performed by Irene Abezgauz, Product 
Manager, Seeker Security. 
For more information please visit www.seekersec.com


-----------------
Irene Abezgauz
Product Manager
Seeker Security
www.seekersec.com
 E-Mail:    irene@xxxxxxxxxxxxx