Researchers are warning that the unpatched security vulnerability in Microsoft's Internet Explorer affects more versions of the browser than previously thought, and that steps users must take to prevent exploitation are harder than first published.
According to an updated advisory from Redmond, the bug that's been actively exploited since Tuesday bites versions 5.01, 6, and 8 of the browser, which is by far the most widely used on the web. A previous warning from Microsoft only said that IE 7 was susceptible to the attacks. IE is susceptible when running on all supported versions of the Windows operating systems, Microsoft also says.
What's more, while there is some protection from Vista's User Account Control, the measure doesn't altogether prevent the attack, according to this post on the Spyware Sucks blog. Microsoft and others have suggested that those who must use IE in the next few weeks set the security level to high for the internet security zone or disable active scripting. These are sensible measures, but they don't guarantee you won't be pwned, according to this post from the Secunia blog.
Secunia goes on to revise what it says is the cause of the vulnerability. Contrary to earlier reports that pinned the blame on the way IE handles certain types of data that use the extensible markup language, or XML, format, the true cause is faulty data binding, meaning exploit code need not use XML.
Microsoft has yet to say whether it plans to issue a fix ahead of next month's scheduled release. For the moment, the volume of in-the-wild attacks remains relatively modest and limited mostly to sites based in China. But because attackers are injecting exploits into legitimate sites that have been compromised, we continue to recommend that users steer clear of IE until the hole has been closed.