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[TLS] Re: FW: I-D Action: draft-kwiatkowski-tls-ecdhe-mlkem-03.txt

Viktor Dukhovni <ietf-dane@dukhovni.org> Mon, 10 March 2025 12:45 UTC

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Date: Mon, 10 Mar 2025 23:45:16 +1100
From: Viktor Dukhovni <ietf-dane@dukhovni.org>
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Subject: [TLS] Re: FW: I-D Action: draft-kwiatkowski-tls-ecdhe-mlkem-03.txt
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On Mon, Mar 10, 2025 at 10:54:16AM +0000, Peter C wrote:

> In ML-KEM, Bob derives b deterministically from m and H(ek).
> If Bob tried to reuse b with a different public key, then the
> re-encryption check would fail during decapsulation. 

Thanks for filling in my "momentary" lapse.  Indeed the server is not
free to choose a fixed "b" (ŷ).  So server-side reuse is not possible as
originally claimed.

-- 
    Viktor.

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