Microsoft is today resolving a nasty vulnerability that targets old versions of Internet Explorer and allowed a user's PC to be overtaken if the browser was steered to select malicious websites. After it was initially found last month, Microsoft offered up a few workarounds and a standalone patch to avoid the flaw, which threatens versions 6, 7, and 8 of Internet Explorer. But today's security update should eliminate the vulnerability for good. Microsoft says that to date, just a "limited number" of customers have fallen victim to the zero-day exploit, but admits " the potential exists that more customers could be affected in the future." As such, the update has been designated critical and will be automatically installed for users that have enabled Automatic Updates on their PCs. Of course, this is also another reminder to keep your browser updated — assuming your situation permits it. IE 9 and 10 were protected from this particular vulnerability from the very beginning.