I am currently assessing the security of Bitlocker from the perspective of an offline attack against a stored password (used to secure the Full Disk Encryption key). My assumption is that the password used to decrypt/determine the FDE key has to be stored somehow on the disk, else it would be impossible to determine if the FDE key is correct or not.
My question is, if, say, a laptop was stolen and it was using Bitlocker to secure the password used to unlock the OS volume, how resistant would it be to an offline attack for the purposes of recovering the password? What techniques/algorithms does it use to protect against an attack like this?
Please note, I am less interested in the recovery of the data on the disk or the FDE key. I am purely interested in this on the basis of how resistant the user's password itself is to an offline attack against a skilled attacker in possession of a stolen laptop.