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Is there any x for which SHA1(x) equals x?

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math

sha1

Is there an x where SHA1(x) == x? I'm looking for a proof or a strong argument against it.

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forki23 Avatar asked Feb 26 '10 09:02

forki23


2 Answers

The same arguments apply here as for the question Is there an MD5 fixed point? I.e. for a randomly chosen function it is about 63%.

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2 revs Avatar answered Oct 02 '22 06:10

2 revs


Read about fixed point attack on this wiki entry One-way compression function - Davies-Meyer

Most widely used hash functions, including MD5, SHA-1 and SHA-2
use Merkle-Damgård construction.

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Nick Dandoulakis Avatar answered Oct 02 '22 04:10

Nick Dandoulakis