Three of the critical vulnerabilities Microsoft patched Tuesday in ActiveX controls for Office were first reported to the company two years ago, according to the security firm that alerted Microsoft of the flaws.

Microsoft has been forced to issue emergency patches for its Windows operating system after researchers discovered a way to bypass a critical security mechanism in the Internet Explorer browser.

As promised, Microsoft today patched six vulnerabilities in Internet Explorer (IE) and Visual Studio with the first "out-of-cycle" update since it plugged a hole last October that the Conficker worm later used to run rampant.

Microsoft today delivered six security updates that patch nine vulnerabilities, fixing two bugs already being used by hackers but leaving one still open to exploit.

Microsoft today warned of a serious security vulnerability in a Spreadsheet ActiveX control that could allow for a drive-by-download attack against vulnerable PCs.