April 2006: Windows Genuine Spyware -- er, Advantage
Yep, three stinkers in one month: Microsoft uses the automatic update channel (and permissions) to install Black Tuesday security patches, as well as non-security-related patches. My favorite example came in late April 2006, when somebody at Microsoft decided automatic update would be a great way to install the new Windows Genuine Advantage, uh, feature.
That version of WGA (in addition to throwing off bogus "not genuine" messages) also installed a component called WGA Notification that phoned home -- sent information to Microsoft about the current computer -- with absolutely no notification to or approval from the customer. Lawsuits ensued. I called it Windows Genuine Spyware.