IT Milk: entry

There is no such thing as “hack-proof digital media,” and the recent cracking of the HD and Blu-ray DVD formats proved this once again. The copy protection in both technologies were supposed to prevent discs from being copied and pirated ever again.

Both HD and Blu-ray use a copy protection scheme called Advanced Access Content System (AACS). Technically Blu-ray is supposed to be the more secure of the two because it uses a single security key. The hacker Muslix64 used a known-plaintext attack to decrypt Blu-ray:

A lot of people try to attack the software, I’m attacking the data!

So I spent more time analysing the data, to look for patterns or something special to mount my known-plaintext attack. Because I know the keys are unprotected in memory, I can skip all the painfull process of code reversal.

I don’t have any Blu-Ray equipment but I was able to recover the keys anyways… because I had access to a memory dump file and a media file.

If all else fails, you can copy entire movies in a series of frames with the “Print Screen” key. This will always remain as a primitive yet fool-proof method.