Today Microsoft announced fourteen updates for security vulnerabilities in Windows, Office, Exchange, and Internet Explorer. Five of the updates are flagged as Critical.
The bulletin summary gets into all the technical details. All you really need to know is that you should install these updates as soon as possible, especially if you use Internet Explorer.
One of the updates provides what is hoped will be a complete fix for a vulnerability that allowed the Stuxnet worm to spread. Microsoft published a fix for this vulnerability in 2010, but the fix was incomplete and the vulnerability remained largely intact.
SANS provides a breakdown of the new updates every month. The information is presented in a way that may be more appealing/useful to some readers.