Microsoft’s Security Updates for October 2010 are divided into 16 bulletins fixing a total of 49 vulnerabilities. Four bulletins have a rating of "Critical" and affect all versions of Windows, including Windows 7 and 2008R2.
One of the critical updates is for Internet Explorer, applicable to version 6, 7 and 8.
Microsoft Office is affected by 2 bulletins, one for Word and one for Excel on all platforms including Mac OS X. Each vulnerability is rated with a severity of "Important", which is Microsoft’s standard rating for file format vulnerabilities, as they require user interaction to be triggered. For the first time the new Microsoft Word 2010 is included in an advisory.
This is the largest update ever on both on the operating system and application side and IT administrators will have to plan well their remediation and testing efforts.