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From: Luke Dashjr <luke@dashjr.org>
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 xor@freenetproject.org
Date: Tue, 3 Jun 2014 04:52:39 +0000
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Subject: Re: [Bitcoin-development] Lets discuss what to do if SHA256d is
	actually broken
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On Tuesday, June 03, 2014 4:29:55 AM xor wrote:
> Hi,
> 
> I thought a lot about the worst case scenario of SHA256d being broken in a
> way which could be abused to
> A) reduce the work of mining a block by some significant amount
> B) reduce the work of mining a block to zero, i.e. allow instant mining.

C) fabricate past blocks entirely.

If SHA256d is broken, Bitcoin as it is fails entirely.

Luke