Digital Rights Management. aka the battle between copyright holders of music and video and the fair use of consumers.
DRM seeks to limit what we all can do with music and video. The problem is the technology isn’t reliable yet and it only affects legitimate consumers. Professional bootleggers have the resources (and motivation) to avoid the protections.
It’s hotting up for Sony and it’s anti copying software that can be found on some of it’s audio CDs. The software uses cloaking techniques to hide itself and prevent removal.
Now virus writers are utilising the software to hide their own code!
The BBC has all the links you need: