BugTraq
Facebook Bug Bounty #19 - Filter Bypass Web Vulnerability Jan 16 2015 12:16PM
Vulnerability Lab (research vulnerability-lab com)
Document Title:
===============
Facebook Bug Bounty #19 - Filter Bypass Web Vulnerability

References (Source):
====================
http://www.vulnerability-lab.com/get_content.php?id=1381

Facebook Security ID: 221374210

Vulnerability Magazine: http://magazine.vulnerability-db.com/?q=articles/2015/01/14/facebook-bug
-bounty-restriction-filter-bypass-vulnerability-id-221374210

Release Date:
=============
2015-01-14

Vulnerability Laboratory ID (VL-ID):
====================================
1381

Common Vulnerability Scoring System:
====================================
3.5

Product & Service Introduction:
===============================
Facebook is an online social networking service, whose name stems from the colloquial name for the book given to students
at the start of the academic year by some university administrations in the United States to help students get to know
each other. It was founded in February 2004 by Mark Zuckerberg with his college roommates and fellow Harvard University
students Eduardo Saverin, Andrew McCollum, Dustin Moskovitz and Chris Hughes. The website`s membership was initially limited
by the founders to Harvard students, but was expanded to other colleges in the Boston area, the Ivy League, and Stanford University.
It gradually added support for students at various other universities before opening to high school students, and eventually to anyone
aged 13 and over. Facebook now allows any users who declare themselves to be at least 13 years old to become registered users of the site.

Users must register before using the site, after which they may create a personal profile, add other users as friends, and exchange messages,
including automatic notifications when they update their profile. Additionally, users may join common-interest user groups, organized by workplace,
school or college, or other characteristics, and categorize their friends into lists such as `People From Work` or `Close Friends`. As of
September 2012, Facebook has over one billion active users, of which 8.7% are fake. According to a May 2011 Consumer Reports survey, there are
7.5 million children under 13 with accounts and 5 million under 10, violating the site`s terms of service.

In May 2005, Accel partners invested $12.7 million in Facebook, and Jim Breyer added $1 million of his own money to the pot. A January 2009
Compete.com study ranked Facebook as the most used social networking service by worldwide monthly active users. Entertainment Weekly included the
site on its end-of-the-decade `best-of` list, saying, `How on earth did we stalk our exes, remember our co-workers` birthdays, bug our friends,
and play a rousing game of Scrabulous before Facebook?` Facebook eventually filed for an initial public offering on February 1, 2012, and was
headquartered in Menlo Park, California. Facebook Inc. began selling stock to the public and trading on the NASDAQ on May 18, 2012. Based on its
2012 income of USD 5.1 Billion, Facebook joined the Fortune 500 list for the first time, being placed at position of 462 on the list published in 2013.

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

Abstract Advisory Information:
==============================
The independent Vulnerability Laboratory Researcher Paulos Yibelo discovered a limitation bypass vulnerability in the official Mobile Site and mobile app (android/ios).

Vulnerability Disclosure Timeline:
==================================
2014-12-10: Researcher Notification & Coordination (Benjamin Kunz Mejri - Evolution Security)
2014-12-11: Vendor Notification (Facebook Security Team - Bug Bounty Program)
2014-12-15: Vendor Response/Feedback (Facebook Security Team - Bug Bounty Program)
2015-01-12: Vendor Fix/Patch (Facebook Developer Team - Reward: Bug Bounty)
2015-01-14: Public Disclosure (Vulnerability Laboratory)

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

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

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

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

Technical Details & Description:
================================
A restriction/limitation bypass web vulnerability has been discovered in the official Facebook Mobile web-application framework.

Facebook limits a name change for 60 days before a new name is applied. The advisory explains how i was able to bypass the restriction
to change my `Alternative name` using parameter session tampering.

First the attacker uses a restricted account (60 day) and review the changes by using a session tamper. By a permanent exchange of the
name values the service updates the name value through the mobile service without usage of the secure restriction mechanism. Remote attackers
are able to bypass the restriction to exploit the vulnerability. The attack vector of the issue is location on the application-side and the
request method to inject is POST.

Using this bug, a local attacker (a logged in user) can impersonate other users to manipulate their friends and change back to
their account name (bypassing the 60day restriction).

The security risk of the filter bypass vulnerability is estimated as high with a cvss (common vulnerability scoring system) count of 3.5.
Exploitation of the filter mechanism vulnerability requires a low privileged web-application user account without user interaction.
Successful exploitation of the bypass issue results in unauthorized account name changes through alternative name inputs.

Request Method(s):
[+] POST

Vulnerable Service(s):
[+] Facebook - Mobile Website
[+] Facebook Apps - Apple iOS & Android

Vulnerable Module(s):
[+] ./settings/account/

Vulnerable Parameter(s):
[+] name

Proof of Concept (PoC):
=======================
The bypass vulnerability can be exploited by remote attackers with a restricted user account and without user interaction.
For security demonstration or to reproduce the security vulnerability follow the provided information and steps below to continue.

Requirements: Attacker needs an account that changed its name and is limited for 60 (x) days before making any other changes

Manual steps to reproduce the vulnerability ...
1. Go to https://m.facebook.com/settings/account/?name&refid=70
2. Click review changes and tamper the request, change the value of
alternative name to anything
3. Continue the request and save the changed value
4. Submit request, then enter your test account password
5. Name value is changed even if time restriction was set
Note: Alternative name shall then be updated too
6. Facebook vulnerability successful exploited!

Reference(s):
https://m.facebook.com/settings/account/?name&refid=70

Security Risk:
==============
The security risk of the restriction/limitation bypass vulnerability in the change name function is estimated as medium. (CVSS 3.5)

Credits & Authors:
==================
Paulos Yibelo (paulosyibelo.com)

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.evolution-sec.com
Contact: admin (at) vulnerability-lab (dot) com [email concealed] - research (at) vulnerability-lab (dot) com [email concealed] - admin (at) evolution-sec (dot) com [email concealed]
Section: magazine.vulnerability-db.com - vulnerability-lab.com/contact.php - evolution-sec.com/contact
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
Programs: vulnerability-lab.com/submit.php - vulnerability-lab.com/list-of-bug-bounty-programs.php - vulnerability-lab.com/register/

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, source code, 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
(admin (at) vulnerability-lab (dot) com [email concealed] or research (at) vulnerability-lab (dot) com [email concealed]) to get a permission.

Copyright © 2015 | Vulnerability Laboratory - [Evolution Security GmbH]�

--
VULNERABILITY LABORATORY - RESEARCH TEAM
SERVICE: www.vulnerability-lab.com
CONTACT: research (at) vulnerability-lab (dot) com [email concealed]
PGP KEY: http://www.vulnerability-lab.com/keys/admin (at) vulnerability-lab (dot) com [email concealed]%280x19
8E9928%29.txt

[ reply ]


 

Privacy Statement
Copyright 2010, SecurityFocus