Re: [TLS] Static DH timing attack

Peter Gutmann <pgut001@cs.auckland.ac.nz> Fri, 11 September 2020 02:25 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: "Salz, Rich" <rsalz@akamai.com>, Achim Kraus <achimkraus@gmx.net>, "tls@ietf.org" <tls@ietf.org>
Thread-Topic: [TLS] Static DH timing attack
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Date: Fri, 11 Sep 2020 02:23:48 +0000
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Subject: Re: [TLS] Static DH timing attack
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Salz, Rich <rsalz@akamai.com> writes:

>Do you mean this because people will confuse DH with ECDHE ?

See my reply to Achim, it's not that but because banning static-ephemeral
(EC)DH will also affect all the cases where it's being applied as it if were
RSA.

Which, given that it's such a footgun would IMHO be a good thing, but others
will probably disagree :-).

Peter.