Microsoft has stated that they will be releasing an out-of-band patch to plug up a critical exploit that affects IE6 - 8 and could allow for remote code execution. The out of band patch is marked as critical and will arrive on January 14th; the update will require you to restart your machine.
This patch will plug up the hole that the Microsoft Security Advisory #2794220 that was reported on December 29th. The exploit that this patch will fix is detailed below:
The vulnerability is a remote code execution vulnerability that exists in the way that Internet Explorer accesses an object in memory that has been deleted or has not been properly allocated. The vulnerability may corrupt memory in a way that could allow an attacker to execute arbitrary code in the context of the current user within Internet Explorer. An attacker could host a specially crafted website that is designed to exploit this vulnerability through Internet Explorer and then convince a user to view the website.
The easiest way to avoid this flaw is to upgrade your browser and, naturally, Microsoft recommends either IE9 or IE10 to help keep your machine protected.
The patch will be pushed out at approximately 10AM PST.
Source: Microsoft