A new vulnerability that puts users of every major web browser at risk, has been discovered by security researchers.

Last week, a pair of security researchers spread the news that a new class of vulnerabilities, called 'clickjacking' puts users of every major browser at risk from possible attack.

Robert Hansen, founder and chief executive of SecTheory LLC and Jeremiah Grossman, chief technology officer at WhiteHat Security, highlighted their discovery of clickjacking at OWASP AppSec 2008.

However, the question on everyone's lips was just how scary clickjacking really is and what should you do to protect yourself?

What is clickjacking?
Good question. Getting to an answer, though, is a little tough, since Hansen and Grossman are keeping virtually all details confidential, at least for now.

"Think of any button on any website that you can get to appear between the browser walls," he said. "Wire transfers on banks, Digg buttons, advertising banners, the list is virtually endless and these are relatively harmless examples. Next, consider that an attack can invisibly hover these buttons below the users' mouse, so that when they click on something they visually see, they actually are clicking on something the attacker wants them to."

In plain English, clickjacking lets hackers and scammers hide malicious stuff under the cover of the content on a legitimate site. You know what happens when a car-jacker takes a car? Well, click-jacking is like that, except that click is the car.

Is clickjacking new?
Nope. Not only is it similar to a cross-site request forgery - a type of vulnerability and attack that has been known since the 1990s - but Hansen acknowledged that clickjacking goes back several years.

Coincidentally or not, Mozilla last week patched a clickjacking vulnerability in Firefox that was, in turn, a variant of a similar flaw in Internet Explorer that Microsoft first patched in 2003, then patched again in 2004.

NEXT PAGE: How does Clickjacking work?

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