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7
votes
3answers
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What is pre-image resistance, and how can the lack thereof be exploited?

What is preimage resistance, and how can the lack thereof be exploited? How is this different from collision resistance? Are there any known preimage attacks that would be considered feasible?
2
votes
1answer
480 views

Why doesn't preimage resistance imply the second preimage resistance?

Let the preimage resistance be defined as »given a hash value $h$, it is hard to find any message $m$ such that $\operatorname{hash}(m)=h$«, and let the second preimage resistance be defined as »given ...