Softpanorama

May the source be with you, but remember the KISS principle ;-)
Contents Bulletin Scripting in shell and Perl Network troubleshooting History Humor

How To Fight Clickjacking

News Recommended Links Cross Site Scripting Chrome Security Helping webmasters with hacked sites
Browser Security   CGI and CGI Security Humor Etc

Top Visited
Switchboard
Latest
Past week
Past month

NEWS CONTENTS

Old News ;-)

How To Fight Clickjacking (Using The Recent Twitter Hijacking As An Example)

Posted by Artem Russakovskii on February 12th, 2009 in Programming, Security, Tutorials, Twitter

Updated: June 9th, 2009

Table Of Contents

image Introduction

Clickjacking is a malicious technique of tricking web users into revealing confidential information or taking control of their computer while clicking on seemingly innocuous web pages. A vulnerability across a variety of browsers and platforms, a clickjacking takes the form of embedded code or script that can execute without the user's knowledge, such as clicking on a button that appears to perform another function (credit: Wikipedia).

Clickjacking is hard to combat. From a technical standpoint, the attack is executed using a combination of CSS and iFrames, which are both harmless web technologies, and relies mostly on tricking users by means of social engineering. Additionally, the only server side technique against clickjacking known to me is "frame breaking", which would cause a legitemate site to break out of any iFrames it may be embedded in. This is not always the desired behavior and is generally frowned upon.

XSS and CSRF are examples of similar malicious web attacks.

Generic Example

In laymen's terms, clickjacking means that it is quite possible for websites to trick you into, for example, clicking a button to show a cute kitty while in reality prompting a deletion of all your hotmail email. A malicious site uses an iFrame (which essentially allows embedding sites within other sites) with hotmail loaded inside and hidden using CSS (which is a web language for styling HTML elements). A button named "Show Me The Next Awwww Kitty" is then placed by the malicious site and positioned below the iFrame layer (manipulated by CSS, yet again). However, because the iFrame is hidden, it looks like the "Aww" button is all you're clicking. Wrong!

image

Latest Example: Twitter

This morning a new, though harmless, epidemic hit twitter. Hundreds and thousands of messages saying "Don't Click: http://tinyurl.com/amgzs6" started showing up. Clicking the link shows a simple page with 1 button:

image Clicking (which I of course did) uses clickjacking to repost the message to your own twitter account. Take a look yourself: http://search.twitter.com/search?q=don%27t+click.

image

All of these are a result of an experiment by some French guys to mess around with twitter and show the effects of clickjacking. Thank you for that, French guys. Creating awareness via the most social platform on the web is the best thing they could do for us.

Twitter rolled out a quick fix, using the very "frame breaking" technique I mentioned earlier. Now any site trying to embed twitter in an iFrame will redirect to it.

Fight Clickjacking

image James Padolsey recently wrote an excellent blog post about clickjacking and mentioned Twitter specifically. Because clickjacking relies mostly on social hacking (i.e. tricking people into clicking malicious links and buttons), Twitter is nothing but a perfect platform. James gives some nice background info and code examples. He correctly highlights, as I did earlier, that clickjacking is not a software bug – it's a malicious technique exploiting harmless technologies.

So how does one fight clickjacking?

At this point the most reliable way is to use Firefox and the NoScript extension. NoScript provides a simple, yet amazingly effective feature, called ClearClick. From their site:

"…it's enabled by default, protecting NoScript users from Clickjacking everywhere: it even remains active if you switch NoScript in the less safe Allow scripts globally mode. How does it work? Clickjacking hides or displaces or partially covers something you wouldn't want to click, if you could see it in its original context. ClearClick does the opposite: whenever you click a plugin object or a framed page, it takes a screenshot of it alone and opaque (i.e. an image of it with no transparencies and no overlaying objects), then compares it with a screenshot of the parent page as you can see it. If the two images differ, a clickjacking attack is probably happening and NoScript raises a "ClearClick warning", showing you the contextualized and "clear" object you were about to click, so you can evaluate by yourself if that was really something you wanted to do."

Did ClearClick work in the earlier twitter attack? Sure did! After I clicked the "Don't click" button Noscript promptly popped up a warning showing the hidden iFrame (since the original malicious page has been removed, I found another similar page from the same author for screenshot purposes).

image

So, even if you don't want to enable NoScript globally, install it anyway, just for ClearClick.

Using a browser other than Firefox? The best technique you should use is, as a general rule, don't click on suspicious buttons and links on pages you are not familiar with. Remember: you're on the Internet and it is full of traps.



Etc

FAIR USE NOTICE This site contains copyrighted material the use of which has not always been specifically authorized by the copyright owner. We are making such material available in our efforts to advance understanding of environmental, political, human rights, economic, democracy, scientific, and social justice issues, etc. We believe this constitutes a 'fair use' of any such copyrighted material as provided for in section 107 of the US Copyright Law. In accordance with Title 17 U.S.C. Section 107, the material on this site is distributed without profit exclusivly for research and educational purposes.   If you wish to use copyrighted material from this site for purposes of your own that go beyond 'fair use', you must obtain permission from the copyright owner. 

ABUSE: IPs or network segments from which we detect a stream of probes might be blocked for no less then 90 days. Multiple types of probes increase this period.  

Society

Groupthink : Two Party System as Polyarchy : Corruption of Regulators : Bureaucracies : Understanding Micromanagers and Control Freaks : Toxic Managers :   Harvard Mafia : Diplomatic Communication : Surviving a Bad Performance Review : Insufficient Retirement Funds as Immanent Problem of Neoliberal Regime : PseudoScience : Who Rules America : Neoliberalism  : The Iron Law of Oligarchy : Libertarian Philosophy

Quotes

War and Peace : Skeptical Finance : John Kenneth Galbraith :Talleyrand : Oscar Wilde : Otto Von Bismarck : Keynes : George Carlin : Skeptics : Propaganda  : SE quotes : Language Design and Programming Quotes : Random IT-related quotesSomerset Maugham : Marcus Aurelius : Kurt Vonnegut : Eric Hoffer : Winston Churchill : Napoleon Bonaparte : Ambrose BierceBernard Shaw : Mark Twain Quotes

Bulletin:

Vol 25, No.12 (December, 2013) Rational Fools vs. Efficient Crooks The efficient markets hypothesis : Political Skeptic Bulletin, 2013 : Unemployment Bulletin, 2010 :  Vol 23, No.10 (October, 2011) An observation about corporate security departments : Slightly Skeptical Euromaydan Chronicles, June 2014 : Greenspan legacy bulletin, 2008 : Vol 25, No.10 (October, 2013) Cryptolocker Trojan (Win32/Crilock.A) : Vol 25, No.08 (August, 2013) Cloud providers as intelligence collection hubs : Financial Humor Bulletin, 2010 : Inequality Bulletin, 2009 : Financial Humor Bulletin, 2008 : Copyleft Problems Bulletin, 2004 : Financial Humor Bulletin, 2011 : Energy Bulletin, 2010 : Malware Protection Bulletin, 2010 : Vol 26, No.1 (January, 2013) Object-Oriented Cult : Political Skeptic Bulletin, 2011 : Vol 23, No.11 (November, 2011) Softpanorama classification of sysadmin horror stories : Vol 25, No.05 (May, 2013) Corporate bullshit as a communication method  : Vol 25, No.06 (June, 2013) A Note on the Relationship of Brooks Law and Conway Law

History:

Fifty glorious years (1950-2000): the triumph of the US computer engineering : Donald Knuth : TAoCP and its Influence of Computer Science : Richard Stallman : Linus Torvalds  : Larry Wall  : John K. Ousterhout : CTSS : Multix OS Unix History : Unix shell history : VI editor : History of pipes concept : Solaris : MS DOSProgramming Languages History : PL/1 : Simula 67 : C : History of GCC developmentScripting Languages : Perl history   : OS History : Mail : DNS : SSH : CPU Instruction Sets : SPARC systems 1987-2006 : Norton Commander : Norton Utilities : Norton Ghost : Frontpage history : Malware Defense History : GNU Screen : OSS early history

Classic books:

The Peter Principle : Parkinson Law : 1984 : The Mythical Man-MonthHow to Solve It by George Polya : The Art of Computer Programming : The Elements of Programming Style : The Unix Hater’s Handbook : The Jargon file : The True Believer : Programming Pearls : The Good Soldier Svejk : The Power Elite

Most popular humor pages:

Manifest of the Softpanorama IT Slacker Society : Ten Commandments of the IT Slackers Society : Computer Humor Collection : BSD Logo Story : The Cuckoo's Egg : IT Slang : C++ Humor : ARE YOU A BBS ADDICT? : The Perl Purity Test : Object oriented programmers of all nations : Financial Humor : Financial Humor Bulletin, 2008 : Financial Humor Bulletin, 2010 : The Most Comprehensive Collection of Editor-related Humor : Programming Language Humor : Goldman Sachs related humor : Greenspan humor : C Humor : Scripting Humor : Real Programmers Humor : Web Humor : GPL-related Humor : OFM Humor : Politically Incorrect Humor : IDS Humor : "Linux Sucks" Humor : Russian Musical Humor : Best Russian Programmer Humor : Microsoft plans to buy Catholic Church : Richard Stallman Related Humor : Admin Humor : Perl-related Humor : Linus Torvalds Related humor : PseudoScience Related Humor : Networking Humor : Shell Humor : Financial Humor Bulletin, 2011 : Financial Humor Bulletin, 2012 : Financial Humor Bulletin, 2013 : Java Humor : Software Engineering Humor : Sun Solaris Related Humor : Education Humor : IBM Humor : Assembler-related Humor : VIM Humor : Computer Viruses Humor : Bright tomorrow is rescheduled to a day after tomorrow : Classic Computer Humor

The Last but not Least


Copyright © 1996-2016 by Dr. Nikolai Bezroukov. www.softpanorama.org was created as a service to the UN Sustainable Development Networking Programme (SDNP) in the author free time. This document is an industrial compilation designed and created exclusively for educational use and is distributed under the Softpanorama Content License.

The site uses AdSense so you need to be aware of Google privacy policy. You you do not want to be tracked by Google please disable Javascript for this site. This site is perfectly usable without Javascript.

Original materials copyright belong to respective owners. Quotes are made for educational purposes only in compliance with the fair use doctrine.

FAIR USE NOTICE This site contains copyrighted material the use of which has not always been specifically authorized by the copyright owner. We are making such material available to advance understanding of computer science, IT technology, economic, scientific, and social issues. We believe this constitutes a 'fair use' of any such copyrighted material as provided by section 107 of the US Copyright Law according to which such material can be distributed without profit exclusively for research and educational purposes.

This is a Spartan WHYFF (We Help You For Free) site written by people for whom English is not a native language. Grammar and spelling errors should be expected. The site contain some broken links as it develops like a living tree...

You can use PayPal to make a contribution, supporting development of this site and speed up access. In case softpanorama.org is down you can use the at softpanorama.info

Disclaimer:

The statements, views and opinions presented on this web page are those of the author (or referenced source) and are not endorsed by, nor do they necessarily reflect, the opinions of the author present and former employers, SDNP or any other organization the author may be associated with. We do not warrant the correctness of the information provided or its fitness for any purpose.

Last modified: September, 12, 2017