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Comment by gruez

6 years ago

which doesn't make sense.

I randomly generated an 8 character alphabetical (all lower case) password "jraxxhwr". According to keepass it has 32 bits of entropy, but the entropy should be 26^8 = 37.6 bits because the search space is all 8 character letter permutations. There's no way you can reduce the search space from 37.6 bits to 32 bits unless you have an oracle that says which characters I used.

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gruez

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FabHK  6 years ago

It does make sense, because the keepass entropy estimate presumably (like the excellent zxcvbn) tries to approximate the empirical distribution, not the theoretical uniform one.

In theory, "68703649" and "12345678" are equally likely to be pulled from the hat, but in practice one is a much better password than the other. You can reduce the search space by trying the passwords with higher (empirical) probability first.