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+Subject: Re: [bitcoin-dev] SHA1 collisions make Git vulnerable to attakcs by

+ third-parties, not just repo maintainers

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+

+On Fri, 2017-02-24 at 00:57 +0100, Aymeric Vitte via bitcoin-dev wrote:

+>

+> I have not worked on this since some time, so that's just thoughts,

+> but maybe it can render things much more difficult

+> than       computing two files until the same hash is found

+>

+

+You basically rely on the idea that specific collisions are more

+difficult to find. This trick or similar tricks will not help. (And

+actually, the more files you add to the hash, the more freedom you give

+the attacker.)

+

+Even if certain collisions are more difficult to find today (which is

+certainly true), the general rule is that someone will prove you wrong

+in a year.

+

+Even if ignore security entirely, switching to new hash function is

+much simpler trying to fix the usage of a broken hash function.

+

+Relying on SHA1 is hopeless. We have to get rid of it.

+

+Best,

+Tim

+

+

+

+