[Dtls-iot] RFC 7925 - Section 16 - Session Hash

Achim Kraus <achimkraus@gmx.net> Wed, 03 June 2020 12:06 UTC

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From: Achim Kraus <achimkraus@gmx.net>
To: dtls-iot@ietf.org
Cc: Hannes Tschofenig <Hannes.Tschofenig@arm.com>, Thomas Fossati <tho.ietf@gmail.com>
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Date: Wed, 03 Jun 2020 14:06:02 +0200
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Subject: [Dtls-iot] RFC 7925 - Section 16 - Session Hash
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Hi Thomas,
Hi Hannes,


I tried to find out, to which list this question should be sent.
According https://www.rfc-editor.org/info/rfc7925 it's dtls-iot.
But the last question there is from 2016. Therefore I added your
addresses directly, I hope that's OK.


https://tools.ietf.org/html/rfc7925#section-16

mentions:

"It is, however, possible that some application-layer protocols will
tunnel other authentication protocols on top of DTLS making this attack
relevant again."


Is there more information about that application-layer risk?
Would RFC 7627 protect against that application-layer risk?

I'm still wondering, if RFC 7627 comes with any benefit,
if only ECDHE or PSK cipher suites are supported anyway.

best regards
Achim