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Due to data loss, I have lost some keyfiles to access some fully encrypted drives. As always there is very important data on the drives and information I better not lose.

The drives have been encrypted using only keyfiles, no additional passwords or whatsoever.

The drives have been encrypted with default settings, that should be AES as encr algo and SHA-512 as hash algo.

Is it possible to reconstruct the keyfile that was generated with one of the latest VeraCrypt versions, I think 1.26.7 or maybe 1.26.14.

Is there somebody who has ever had success in reconstructing a keyfile?

Tell me if you need more specific info.

Giacomo1968
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user2642403
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2 Answers2

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It is not possible, and indeed that's the entire point of keyfiles.

The parts that actually serve as the encryption key (which in the case of VeraCrypt is the whole file) are always generated from random data, deliberately so that the key could not be guessed (not without already knowing like 90% of it).

No part of the actual 'key' is determined from the VeraCrypt version, nor from the encrypted volume's metadata, nor from any other "known" sources.

So the only way to reconstruct a keyfile would be to guess all possible keys until you find a working one – which is not practical for AES as it would take half the time and energy of the universe (or maybe a quantum computer for AES128, but still not for AES256).

grawity
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Is it possible to reconstruct the keyfile?

No, that's not possible. Veracrypt uses high-grade encryption and without the key there's no way to break that encryption in a sane amount of time. After all, that's the point of data encryption. If you haven't backed up the keyfile and there's no rescue disk, then that's that.

No data stored on an encrypted volume can be read (decrypted) without using the correct password/keyfile(s) or correct encryption keys.

https://www.veracrypt.fr/en/Introduction.html

Zac67
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