Score:-1

Is it possible to have collision resistance but not pre-image and 2nd pre-image resistance?

in flag

I have studied cryptographic hash functions quite a lot, but have not completely understood whether it is possible to have collision resistance but not pre-image and 2nd pre-image resistance at the same time.

Is it possible?

Please answer this question with a general example.

Patriot avatar
cn flag
Please see [this link](https://security.stackexchange.com/q/69405) and [this](https://stackoverflow.com/q/28378326).
Score:3
in flag

No, any second preimage creates a collision. So collision resistance implies 2nd preimage resistance.

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