4 ms·

AACS is designed to expect some keys will leak, so they have revocation mechanism for new titles.

• gjsman-1000 4y ago
  Right... but here's the hilarious (for a pirate) bit. AACS knew player keys would leak and hardened their system against it... but they didn't realize that BDXL readers, which existed before 4K Blu-ray was released, could actually read 4K discs with modified firmware. Also, said BDXL readers had no Secure Boot and could be easily modified. With a modified player (which they didn't expect), you can read directly from the disc the data, which is (at the end of the encryption chain) encrypted with a per-disc key that is unchangeable. Normally this wouldn't matter because you can't read the disc directly - but with the modified player, you can. The player key goes through a long, complex process to end up with that unchangeable, unrevokable unique disc key. The pirates solution? Keep the drive keys when they discover them secret, and just generate the disc-unique keys and post them online for every disc. Then, with the modified drives, every disc in the list is permanently broken, and AACS LA has no idea what drive key is leaked and can't revoke it. And so here we are... AACS LA doesn't know which drive key the pirates are using, and when disc keys are generated, the disc is cracked forever. Worst of all worlds for AACS...