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Microsoft boasts 'out of box' IE8 clickjack protection

Imperfect solution to perfect storm

By Dan Goodin, 27 Jan 2009

Analysis

Microsoft has beefed up its latest Internet Explorer browser with an "out of the box" feature that it says will protect users against a serious class of attacks that allows maliciously controlled websites to manipulate the links visitors click on.

The new measure, baked into Redmond's first release candidate for IE8, blocks so-called clickjacking attacks, a threat that security researchers warn plagues users of every major browser.

Once lured to a malicious address, a user may think she's clicking on a link that leads to Google - when in fact it takes her to a money transfer page, a banner ad that's part of a click-fraud scheme, or any other destination the attacker chooses. Because it exploits architectural flaws in the internet's core, clickjacking has proved an extremely vexing problem to fix.

Microsoft's readiness to tackle the vulnerability is commendable, but some security watchers are already questioning its approach. The protection, it turns out, relies on special tags webmasters must put on their pages that prevent clickjacking by returning an error message when malicious links are detected. In other words, for the protection to be effective, billions of webpages will need to be altered with tweaks, and the average user will have no way of knowing whether a given site has implemented them.

"The bad news for IE enthusiasts is that they've got no magic 'out of the box' protection, despite the press releases" from Microsoft, security researcher Giorgio Maone wrote here. "All the sites to be protected must already have adopted a new proprietary hack, i.e. something no end-user can verify, let alone enforce (so long for the 'consumer-ready' label)."

Of course, as creator of NoScript - a security add-on for Firefox that offers important clickjacking protections not available in other browsers - Maone isn't the most non-partisan of commentators. But plenty of other security researchers also question Microsoft's reliance on special tags.

"That's a major limitation," said Jeremiah Grossman, CTO of web security firm WhiteHat Security, and one of the researchers who first sounded the alarm on clickjacking. "If that's the only feature they've added, it doesn't allow users to protect themselves" against the vulnerability.

Microsoft representatives said they are drafting a blog post that will give additional details about the protections. "In the meantime, I can tell you that in order to help users browse more safely, regardless of their choice of browser, Microsoft worked with browser vendors Opera, Mozilla, Google, and Apple to get feedback and input on our implementation of the clickjacking tag before shipping Internet Explorer 8 RC1," a spokeswoman wrote in an email to El Reg.

The rift points to pros and cons of the different approaches at Microsoft and Mozilla, the No. 1 and No. 2 browser developers respectively. Mozilla, which has long fostered a robust ecosystem that spawns thousands of plug-ins, often relies on NoScript, Adblock Plus, and other add-ons to offer security protections. The modular approach generally allows Firefox users a wider range of tools and security protections than is available to IE users.

But because they have to be downloaded, installed, and regularly updated, and because they often have cryptic support documentation, such add-ons aren't yet suitable for the masses. Microsoft's approach, whatever its faults, is designed to require little or no interaction on the part of users. Meanwhile, updates Adobe made to Flash in October fixed some but not all clickjacking exploits.

So for now, we're stuck with a patchwork of imperfect and incomplete fixes for an architectural flaw that has the potential to threaten trust as we know it on the internet. You can expect a lot more kludges before this problem is ultimately solved. ®