Skip to main content
1 of 4
Peter Harmann
  • 7.9k
  • 5
  • 22
  • 28

First and foremost, I assume you mean AES, not RSA. I also assume integrity is of no concern/is provided in other way, as VeraCrypt does not provide data integrity checks. Furthermore, I assume the attackers only have one version of the data, as XTS is apparently weaker to analysis of changes. I also don't consider side-channels as I assume your security is perfect in other areas.

Second of all, if you have good enough password, it should not help to have key-files added. Though technically, if I am not mistaken, you may actually want to use 128 characters to achieve the full potential of the three nested ciphers, because each cipher needs 256 bit key, so you want 768 bits of entropy. This is one of the very rare cases where passphrase longer than 64 random characters make sense.

As for cracking the keys using brute force, I don't believe it would be possible before the heat-death of the universe regardless of the advancements in technology and increase in availability. I recently estimated here, that it is possible to crack 14 bit AES key in a day on a good CPU. Getting to even 128 bits seems unfeasible even in centuries, without a massive breakthrough. And almost 512 bits are just near impossible. It is currently believed not even quantum computers will actually break symmetric ciphers.

The other way this may be broken however is breaking of the underlying ciphers. AES-256 already has a known issue, because of which it does not provide full 256 bits of protection. If these ciphers get broken enough (their protection twiddled down enough, it may be feasible to break this in the fat future). However, it is impossible to accurately predict, whether and how much will these ciphers be broken. I would predict, that using three good ciphers should provide protection for at least several decades, probably a lot more.

Peter Harmann
  • 7.9k
  • 5
  • 22
  • 28