Facebook BugBounty #2 - Persistent Web Vulnerabilities

Document Title:
===============
Facebook BugBounty #2 - Persistent Web Vulnerabilities


References (Source):
====================
http://www.vulnerability-lab.com/get_content.php?id=239
http://www.vulnerability-lab.com/get_content.php?id=277


Release Date:
=============
2011-09-19


Vulnerability Laboratory ID (VL-ID):
====================================
239


Product & Service Introduction:
===============================
Facebook is a social networking service and website launched in February 2004, operated and privately owned 
by Facebook, Inc. As of July 2011, Facebook has more than 750 million active users.  Users may create 
a personal profile, add other users as friends, and exchange messages, including automatic notifications when 
they update their profile. Facebook users must register before using the site. Additionally, users may join 
common-interest user groups, organized by workplace, school or college, or other characteristics. 

(Copy of the Vendor Website: http://en.wikipedia.org/wiki/Facebook)


Abstract Advisory Information:
==============================
Vulnerability Lab Team discovered multiple persistent web vulnerabilities in a main module of the facebook website.


Vulnerability Disclosure Timeline:
==================================
2011-08-01:	Vendor Notification
2011-08-04:	Vendor Response/Feedback
2011-09-10:	Vendor Fix/Patch
2011-09-16:	Public or Non-Public Disclosure


Discovery Status:
=================
Published


Affected Product(s):
====================

Exploitation Technique:
=======================
Remote


Severity Level:
===============
Medium


Technical Details & Description:
================================
Multiple persistent input validation vulnerabilities are detected on the Facebook vendor website.
The vulnerability allows an remote attacker to implement malicious persistent script codes 
in a preview listing module of facebook. The successful exploitation of the vulnerability can lead 
to session hijacking, events module content manipulation, implementation of persistent malware 
links & redirection to external malicious websites without authorization. The bug is located 
in a preview listing module in the description of a location.

Vulnerable Module(s):
							[+] Events - Change Listing Preview 

Affected Input(s):
							[+] Where? & What are you plaining? What are you plaining?

Pictures:
							../1.png


Proof of Concept (PoC):
=======================
The vulnerability can be exploited by remote attackers. For demonstration or reproduce ...

PoC: "><iframe src=a onload=alert("PERSISTENT_XSS") <

or ...

%22%3E%3C%69%66%72%61%6D%65%20%73%72%63%3D%61%20%6F%6E%6C%6F%61%64%3D%61%6C
%65%72%74%28%22%50%45%52%53%49%53%54%45%4E%54%5F%58%53%53%22%29%20%3C


Solution - Fix & Patch:
=======================
Restrict/Parse the input field validation & clean up the output preview listing.


Security Risk:
==============
The security risk of the persistent web vulnerabilities are estimated as medium(+).


Credits & Authors:
==================
Vulnerability Research Laboratory - Levent Kayan (noptrix)


Disclaimer & Information:
=========================
The information provided in this advisory is provided as it is without any warranty. Vulnerability-Lab disclaims all warranties, 
either expressed or implied, including the warranties of merchantability and capability for a particular purpose. Vulnerability-
Lab or its suppliers are not liable in any case of damage, including direct, indirect, incidental, consequential loss of business 
profits or special damages, even if Vulnerability-Lab or its suppliers have been advised of the possibility of such damages. Some 
states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation 
may not apply. We do not approve or encourage anybody to break any vendor licenses, policies, deface websites, hack into databases 
or trade with fraud/stolen material.

Domains:    www.vulnerability-lab.com   	- www.vuln-lab.com			       - www.vulnerability-lab.com/register
Contact:    [email protected] 	- [email protected] 	       - [email protected]
Section:    video.vulnerability-lab.com 	- forum.vulnerability-lab.com 		       - news.vulnerability-lab.com
Social:	    twitter.com/#!/vuln_lab 		- facebook.com/VulnerabilityLab 	       - youtube.com/user/vulnerability0lab
Feeds:	    vulnerability-lab.com/rss/rss.php	- vulnerability-lab.com/rss/rss_upcoming.php   - vulnerability-lab.com/rss/rss_news.php

Any modified copy or reproduction, including partially usages, of this file requires authorization from Vulnerability Laboratory. 
Permission to electronically redistribute this alert in its unmodified form is granted. All other rights, including the use of other 
media, are reserved by Vulnerability-Lab Research Team or its suppliers. All pictures, texts, advisories, sourcecode, videos and 
other information on this website is trademark of vulnerability-lab team & the specific authors or managers. To record, list (feed), 
modify, use or edit our material contact ([email protected] or [email protected]) to get a permission.

    				   	Copyright © 2012 | Vulnerability Laboratory