The infected Sony CDs forces customers to play its CDs using the program supplied. It seems that this program has infriged on copyrights, as it includes components from an open-source project — a MP3 player/encoder called LAME. Per licensing rules, if open-source software is used, there needs to be clear indication made so that it can be shared with others. And you can probably guess, of course, that there is no indication whatsoever on the packaging that would indicate this.
Moreover, if the source code of the open-source project is tightly woven into a single executable program (as it appears to be the case with this media player program), then the program itself must be made "open-source".