The software giant did say, however, that it does not appear hackers have begun using the exploit.
While they continue to work on a permanent fix, the company has created a workaround for the bug.
The BBC explains the "bug revolves around the way that IE manages a computer's memory when processing Cascading Style Sheets - a widely used technology that defines the look and feel of pages on a website."
Hackers have long used IE's memory management to inject their own code, usually leading to a hijack of the vulnerable computer.
For now, IE users are being told to "use a protection system known as the Enhanced Mitigation Experience Toolkit."
Rik Ferguson, of Trend Micro says:
"As vulnerabilities go, this kind is the most serious as it allows remote execution of code. This means the attacker can run programs, such as malware, directly on the victim's computer. It is highly reminiscent of a vulnerability at the same time two years ago which prompted several national governments to warn against using IE and to switch to an alternative browser."
Written by: Andre Yoskowitz @ 24 Dec 2010 3:48