This is another new twist with the a Netcraft: Witty Worm targeting Black Ice users. What's nasty about this particlar attack is that it also can disable a machine. The way it does it means you can be infected and sugger damage long before you really become aware you have an issue.
Just more proof, as if it's needed, that users need to keep bang up to date and that defense in depth is a useful strategy. I suspect a lot of home users will get stung by this, and won't even know how it happened.