An encrypted ZIP file can have two correct passwords

Re:An encrypted ZIP file can have two correct passwords – he... by V__ on Sunday August 21, 2022 @05:26PM (#32544617)

Since hash functions are fixed-length, aren't there always infinitely many collisions and therefore passwords which would work?

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Re:An encrypted ZIP file can have two correct passwords – he... by omoikane on Sunday August 21, 2022 @06:19PM (#32545054)

In theory yes, but finding SHA1 collisions is nontrivial. shattered.io has one, but they used up quite a bit of compute to get it.

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Re:An encrypted ZIP file can have two correct passwords – he... by riotman on Sunday August 21, 2022 @05:32PM (#32544673)

Unless it's invertible.

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Re:An encrypted ZIP file can have two correct passwords – he... by PeterisP on Sunday August 21, 2022 @07:09PM (#32545414)

Hash functions can't be invertible due to pigeonhole principle, as there are more possible inputs than possible outputs for a fixed-size hash.

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