Microsoft today is warning computer users to protect their PCs after critical flaws were found in some versions of Windows, Internet Explorer and Outlook Express.

Home users are particularly open to attack, because they don't often download the latest security patches from Microsoft, and may not be running a personal firewall

Microsoft Vunerabilities
Critical: Windows HTML help
Critical: Windows Task Manager
Important: Microsoft Windows Utility Manager
Important: POSIX Subsystem of Microsoft Windows
Important: Internet Information Services, Microsoft Windows

Microsoft patch info here