An official patch for the WMF vulnerability has been released today, a few days before the planned release date of January 10th. Make sure you install it via Windows Update immediately.

Microsoft announced that it would release a security update to help protect customers from exploitations of a vulnerability in the Windows Meta File (WMF) area of code in the Windows operating system on Tuesday, January 2, 2006, in response to malicious and criminal attacks on computer users that were discovered last week.

Microsoft will release the update today on Thursday, January 5, 2006, earlier than planned.

Microsoft originally planned to release the update on Tuesday, January 10, 2006 as part of its regular monthly release of security bulletins, once testing for quality and application compatibility was complete. However, testing has been completed earlier than anticipated and the update is ready for release.

From the Technet Security Bulletin.