Re: [Curdle] Looking for comments on draft-ietf-curdle-ssh-kex-sha2

Hubert Kario <hkario@redhat.com> Thu, 26 November 2020 17:26 UTC

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From: Hubert Kario <hkario@redhat.com>
To: Tero Kivinen <kivinen@iki.fi>
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Date: Thu, 26 Nov 2020 18:26:10 +0100
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Subject: Re: [Curdle] Looking for comments on draft-ietf-curdle-ssh-kex-sha2
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On Thursday, 26 November 2020 18:09:41 CET, Tero Kivinen wrote:
> Hubert Kario writes:
>>> The diffie-hellman-group14-sha1 exchange was a mandatory to implement
>>> MUST and is now a SHOULD. Similarly for gss-group1-sha1-*
>> 
>> no, I think it should be SHOULD NOT, the sha-1 disqualifies it
>
> If I remember right about ssh key exchange, it does not rely on the
> collision resistance at all, it relies on the 2nd preimage resistance,

I don't think this is the case:
https://hal.inria.fr/hal-01244855/document

-- 
Regards,
Hubert Kario
Senior Quality Engineer, QE BaseOS Security team
Web: www.cz.redhat.com
Red Hat Czech s.r.o., Purkyňova 115, 612 00  Brno, Czech Republic