Ziff Davis is reporting that a UK group has released an exploit for IE that could allow a hacker to take complete control of a program by expoiting a hole in the Javascript Window() command.

Exploit code for a critical flaw in fully patched versions of Microsoft Corp.’s Internet Explorer browser has been released on the Internet, putting millions of Web surfers at risk of computer hijack attacks.

The zero-day exploit, posted by a U.K.-based group called “Computer Terrorism,” could allow a remote hacker to take complete control of a Windows system if the victim simply browses to a malicious Web site.

You can test your computer for the exploit by visiting a site (linked in the article) that launches the Windows Calculator on your computer.