How HD-DVD Copy Protection Was (Possibly) Defeated

Over the last couple of months, there have been reports of HD-DVD and Blu-ray copy protection being defeated and bypassed. I can’t say I’m an expert in this area and I haven’t slogged through the public AACS documents. While it’s unclear if these methods (and keys) are temporary “solutions” or if they will permanently bypass AACS, one hacker describes his methodology for teasing out the data:

This gave me an idea: what I wanted to do is “record” all changes in this part of memory during startup of the movie. Hopefully I would catch something interesting. In the end I did something a little more efficient: I used the hd dvd vuk extractor and adapted it to slow down the software player (while scanning its memory continuously) and at the very moment the Media Key (which I now knew: my bottom-up approach really paid off here) was detected it halted the player. I then made a memdump with WinHex. I now had the feeling I had something. And I did. Not surprisingly the very first C-value was a hit. I then checked if everything was correct, asked for confirmation and here we are.