Re: [TLS] Deprecating TLS 1.0, 1.1 and SHA1 signature algorithms

Peter Gutmann <pgut001@cs.auckland.ac.nz> Tue, 12 January 2016 02:07 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: Watson Ladd <watsonbladd@gmail.com>
Thread-Topic: [TLS] Deprecating TLS 1.0, 1.1 and SHA1 signature algorithms
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Date: Tue, 12 Jan 2016 02:06:57 +0000
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Subject: Re: [TLS] Deprecating TLS 1.0, 1.1 and SHA1 signature algorithms
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Watson Ladd <watsonbladd@gmail.com>; writes:

>SHA-1 collisions have not yet been found. Marc Stevens has published
>algorithms he claims reduce the complexity of finding these collisions to
>feasible amounts, but they have not yet been run. However, free-start
>collisions have been found, as have ways to modify constants in the SHA-1 IV
>to get collisions.

I'm aware of that (and related) work, but this is about finding
multicollisions in MD5 || SHA1.

Peter.