Microsoft technology designed to protect Internet Explorer users from a powerful new web-based attack will not fix the problem, security experts have claimed.
Microsoft released the technology as part of an early release candidate test version of its next-generation Internet Explorer 8 browser, saying that the company had developed "consumer-ready" protection for an attack known as clickjacking.
In clickjacking, attackers use special web programming to trick victims into clicking web buttons without realising it. The attack is hard to pull off, but at its worst, clickjacking can do some very nasty things, such as execute stock trades on financial websites, change router or firewall configurations, or even force someone to download unwanted software.
The problem is so vast that security experts worry that Microsoft's approach, which works only when website developers add special tags to their pages that prevent their own web buttons from being misused, may end up giving IE users a false sense of security.
"It's not a solution to clickjacking by any stretch of the imagination. It's a vaguely mitigating factor for the very few people who use IE8," said Robert Hansen, CEO of the SecTheory consultancy, and one of the people who first reported the issue to Microsoft. "But it's interesting that they're taking it seriously."
While some websites will certainly use Microsoft's technology to prevent their IE visitors from being hit with clickjacking, there are simply too many other areas where HTML code is unlikely to be updated and hackers could launch attacks - targeting router administrative interfaces or corporate applications, or going after websites that have not gotten around to implementing Microsoft's fix.
"This is a solution which, even if everyone decides that this is the right way to do things, it still will take years and years of education," Hansen said.
Worse, some users might mistakenly think they are protected from the attack just because they are using IE, according to Giorgio Maone, the developer of the Firefox NoScript plugin, which is generally considered the best protection from many web-based attacks, including clickjacking.
"The bad news for IE enthusiasts is that they've got no magic 'out of the box' protection," he wrote on his blog Tuesday. "True, it doesn't require any 'browser add-on' ... but it comes with an even more strict requirement: 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."
NoScript lets users selectively block the use of scripting languages within the Firefox browser. Because clickjacking requires scripting, the attack doesn't work when NoScript is enabled.
For months, Maone's plug-in has been the best-known technology for thwarting clickjacking. With the IE 8 test code, however, Microsoft finally has its own alternative.
To help the situation, Maone is developing a compatibility feature so that NoScript users will be able to take advantage of the same Web code used by IE, and he is now lobbying to have this feature included in an upcoming version of Firefox.
Hansen and Maone also criticised Microsoft for holding off on technical details of the technology. "Even though they implemented that, they haven't given guidance on how to actually use it," Hansen said.
In an e-mailed statement, Microsoft said that it planned to put up a blog post on the anti-clickjacking feature sometime this week and that it had worked with all major browser vendors "to get feedback and input on our implementation of the clickjacking tag before shipping Internet Explorer 8 RC1."
That post might be helpful. As things stand now, it looks like "the feature doesn't allow the user to protect themselves," said Jeremiah Grossman, chief technology officer with White Hat Security.
Hansen said that Microsoft developers first proposed their IE8 clickjacking fix several months ago when he first described the problem to them. "I dismissed it as not a long-term, viable solution to clickjacking," he said.