Microsoft - December 2012 Security Updates available
Several protective updates are available for Windows, IE, Word, Exchange, and other products.
Many of these are rated as Critical and users should promptly update their systems.
Microsoft - December 2012 Security Update home page
http://technet.microsoft.com/en-us/security/bulletin/ms12-dec
ISC - EXCELLENT COMPLEMENTARY ANALYSIS
https://isc.sans.edu/diary/Microsoft+December+2012+Black+Tuesday+Update+-+Overview/14683