Microsoft (MS) yesterday issued a ‘critical’ Windows patch — outside its regular, monthly Security Bulletin cycle. The last time that happened was back in April, 2007.

The MS special Security Bulletin describes the vulnerability being addressed as one of those flaws that could allow a hacker to take control of your computer.

The problem affects Windows XP and Vista, as well as certain versions of Windows Server and Windows 2000.

You can get the patch to fix this problem at the Windows Update site. Just click ‘Windows Update’ in your Start menu and follow the instructions at the site.

Observers say that, when MS issues a security update ‘out of band’ like this, it’s an indication that MS considers the problem it addresses very serious.