I am interested in the recent Apple case where FBI wants to get access, but they say it's not technically possible other than creating a new OS (or I guess just modifying the existing one). More details of Apple response is here.
What I do not understand is how is it not possible to brute-force the password? If you type it in the screen, then there is a limited number of attempts, right. But the password has to be stored somewhere for verification (even if it's KDF or something). Can't FBI extract the hash from the hard drive and start their brute-force? I guess their colleagues from NSA can help them with that and if password is not too good, it won't take too long.