This update just automatically installed on my machine.
When I search microsoft.com for KB912919 nothing's found.
Can anyone tell me what this security update does?
As far as I know this is an early release of the regularly monthly scheduled update. The early release due to a vulnerability compromise of anyone's system that can be carried in by a WMF (windows media file) which can attack or be later executed. Just type in "WMF vulnerability" in the search field in the forum and you'll find more expert definitions of this.
