This is the biggest worm attack for years, and in theory could hit 350 million PCs or thereabouts. However, in spite of this “amazing” worm “skyrocketing,” F-Secure says: “Downadup infections appear to have peaked during the week.” Its latest reported estimate is only 15 million, which is not all that impressive for something that was first seen last November, and should be able to double every day.
Maybe the next version(s) will do better. But let's hope not.
Of course, there's no real reason why anyone should have Downadup/Conflickr: Microsoft patched that security hole last October with Microsoft Security Update MS08-067 (KB958644), and on October 25, I posted Microsoft releases critical patch, extra to Windows update to tell you to install it. I'm sure there are a few unlucky souls among the estimated 15m victims, but I suspect most have got Downadup/Conflickr because they are too lazy or too dim to install Windows Updates, or they're running pirated copies of Windows.
Or perhaps it's because previous updates have hosed their computers (see post #30 above) or because something they installed happened to uninstall the patch.
Oh wait, that could never happen!
Er, well...maybe it could, since it's happened before.