Beware of emails that claim to be Microsoft Security Bulletins
The SANS Institute is warning of a Fake Microsoft Security Bulletin that leads to the installation of a malicious browser add-on.
Microsoft issues patches on a regular monthly schedule and information is always available from the Microsoft Security site at http://www.microsoft.com/security/. This provides links to the latest security bulletins and to Windows Update.
There's also a page on How to tell whether a security e-mail message is really from Microsoft.
The general rule is never to download a security update (whether from Microsoft or anybody else) directly by clicking on a link in email. Only download these updates from the company's Web site, which usually means Windows Update.
