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I've been getting into forensics and penetration testing lately and hoping someone can explain what the below data is and how it might be used to perform a bruteforce (hashcat) attacks against macbooks.

More specifically, what is "VEK Wrpd", "KEK Wrpd", "HMAC", and "PW Key"? And can they be used to reproduce the FileVault password if it's guessed correctly?

I used apfs-fuse to dump the data:

$ ./apfs-fuse -d 16 /dev/sda2/ /path/to/mount

Device /dev/sda2 opened. Size is 250790436864
starting LoadKeybag
 all blocks verified
 header has type 6b657973
Volume macOS1 is encrypted.
Password hint: looking for key type 3 for volume 1342XXXX-XXXX-XXXX-XXXX-XXXXXXXX4251 in m_container_bag
Trying to load key bag from recs_block
starting LoadKeybag
 all blocks verified
 header has type 72656373
Password hint: looking for key type 4 for volume 1342XXXX-XXXX-XXXX-XXXX-XXXXXXXX4251 in recs_bag
Enter Password: 
GetVolumeKey: Dumping container keybag.
Dumping Keybag (keys)

Version :    2
Keys    :    2
Bytes   :       e0

Key 0:
UUID    : 1342XXXX-XXXX-XXXX-XXXX-XXXXXXXX4251
Type    :    3 [Keybag Ref]
Length  :   10
Unknown :        0

Block   :           7c1f57
Count   :                1

Key 1:
UUID    : 1342XXXX-XXXX-XXXX-XXXX-XXXXXXXX4251
Type    :    2 [VEK]
Length  :   7c
Unknown :        0

[Blob Header]
Unk 80  : 0
HMAC    : 106BXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX9921
Salt    : 5493XXXXXXXX1F47

[VEK]
Unk 80  : 0
UUID    : 1342XXXX-XXXX-XXXX-XXXX-XXXXXXXX4251
Unk 82  :        0    1 9e b1
VEK Wrpd: 06391FA9XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX552582F2



GetVolumeKey: looking for key type 3 for volume 1342XXXX-XXXX-XXXX-XXXX-XXXXXXXX4251 in m_container_bag
 key found
 data size matches that of key_extent_t
Trying to load key bag from recs_block
starting LoadKeybag
 all blocks verified
 header has type 72656373
Volume key bag loaded successfully. Dumping contents.
Dumping Keybag (recs)

Version :    2
Keys    :    3
Bytes   :      220

Key 0:
UUID    : 257AXXXX-XXXX-XXXX-XXXX-XXXXXXXX7975
Type    :    3 [KEK]
Length  :   94
Unknown :        0

[Blob Header]
Unk 80  : 0
HMAC    : F047XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXF6A8
Salt    : 630CXXXXXXXX268

[KEK]
Unk 80  : 0
UUID    : 257AXXXX-XXXX-XXXX-XXXX-XXXXXXXX7975
Unk 82  :        0    2 9e b1
KEK Wrpd: BB7FXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX07F8
Iterat's: 100000
Salt    : 863CXXXXXXXXXXXXXXXXXXXXXXXX2F51


Key 1:
UUID    : CDF5XXXX-XXXX-XXXX-XXXX-XXXXXXXXE4CA
Type    :    3 [KEK]
Length  :   94
Unknown :        0

[Blob Header]
Unk 80  : 0
HMAC    : 5A2AXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXAEB8
Salt    : BFBFXXXXXXXX5FD6

[KEK]
Unk 80  : 0
UUID    : CDF5XXXX-XXXX-XXXX-XXXX-XXXXXXXXE4CA
Unk 82  :        0    2 9e b1
KEK Wrpd: 43A8XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX5E07
Iterat's: 117590
Salt    : 8751XXXXXXXXXXXXXXXXXXXXXXXXB0DA


Key 2:
UUID    : EBC6XXXX-XXXX-XXXX-XXXX-XXXXXXXXECAC
Type    :    3 [KEK]
Length  :   94
Unknown :        0

[Blob Header]
Unk 80  : 0
HMAC    : 9F92XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX5706
Salt    : E363XXXXXXXXCC09

[KEK]
Unk 80  : 0
UUID    : EBC6XXXX-XXXX-XXXX-XXXX-XXXXXXXXECAC
Unk 82  :        0    2 9e b1
KEK Wrpd: CF35XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXEC04
Iterat's: 127270
Salt    : 3780XXXXXXXXXXXXXXXXXXXXXXXXA2E7



PW Key  : EE62XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX6AB5
KEK Wrpd: BB7FXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX07F8
KEK     : A60EXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX4D78
KEK IV  : F7ECXXXXXXXX202A

PW Key  : 6363XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX6191
KEK Wrpd: 43A8XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX5E07
KEK     : EB9FXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXD6F9
KEK IV  : 5932XXXXXXXX4ACB

PW Key  : 6B62XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXEEFF
KEK Wrpd: CF35XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXEC04
KEK     : B579XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXAD90
KEK IV  : A3E7XXXXXXXXCA4F

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