Washington Post. 29 May
A routine security update for a Microsoft Windows component installed on tens of millions of computers has quietly installed an extra add-on for an untold number of users surfing the Web with Mozilla's Firefox Web browser.
Earlier this year, Microsoft shipped a bundle of updates known as a "service pack" for a programming platform called the Microsoft .NET Framework, which Microsoft and plenty of third-party developers use to run a variety of interactive programs on Windows.
The service pack for the .NET Framework, like other updates, was pushed out to users through the Windows Update Web site. A number of readers had never heard of this platform before Windows Update started offering the service pack for it, and many of you wanted to know whether it was okay to go ahead and install this thing. Having earlier checked to see whether the service pack had caused any widespread problems or interfered with third-party programs -- and not finding any that warranted waving readers away from this update -- I told readers not to worry and to go ahead and install it.
http://voices.washingtonpost.com/securityfix/2009/05/microsoft_update_quietly_insta.html?wprss=securityfix--------------------
Microsoft is not the only one fiddling with your browser. I just found 'Java Quick Starter' had been secretly installed among my Firefox add-ons with no way to uninstall, only disable it via the add-ons control window. To uninstall, you need to open Java in Control Panel.