Microsoft has posted a security bulletin advance notification for their patches coming up this month. This month there"s a hefty amount of updates listed as "critical", so it"s probably best to be aware of these and be prepared to install them.
Here"s a list of the patches, and the software they affect:
Bulletin Identifier: Windows 1
Rating: Important
Affected Software: Microsoft Windows, Microsoft Office
Purpose: Prevent remote code execution
Bulletin Identifier: Windows 2
Rating: Critical
Affected Software: Microsoft Windows
Purpose: Prevent remote code execution
Bulletin Identifier: Windows 3
Rating: Critical
Affected Software: Microsoft Windows
Purpose: Prevent remote code execution
Bulletin Identifier: IE
Rating: Critical
Affected Software: Microsoft Windows, Internet Explorer
Purpose: Prevent remote code execution
Bulletin Identifier: Excel
Rating: Critical
Affected Software: Microsoft Office
Purpose: Prevent remote code execution
Bulletin Identifier: Windows 4
Rating: Important
Affected Software: Microsoft Windows
Purpose: Prevent elevation of privilege
Bulletin Identifier: ISA
Rating: Important
Affected Software: Microsoft Forefront Edge Security
Purpose: Prevent denial of service
Bulletin Identifier: Windows 5
Rating: Moderate
Affected Software: Microsoft Windows
Purpose: Prevent elevation of privilege
All those patches list above give rather brief overviews, and there"s too much information to go into detail on each operating system, so please visit the Microsoft Security Bulletin page linked above if you wish to get specifics. Along with these patches, there will be an updated version of Microsoft"s Malicious Software Removal Tool.
The patches are expected to be released on April 14th, 2009, so stay alert. The updates should automatically download themselves, but if they don"t you can always find "Windows Update" in the Start menu of your operating system.