Subject: [Seat] Re: Regarding symbolic analysis of draft-fossati-seat-early-attestation-06
From: Songbo Bu <[email-masked]>
To: [email-masked], [email-masked]
Cc: [email-masked]
Date: Mon, 10 Aug 2026 10:58:52 +0800
List-Id: "Secure Evidence and Attestation Transport (SEAT) WG" <seat.ietf.org>

Nathanael,

Thank you for the answers. I feel like some questions were not
narrowly answered. Please answer as narrowly as possible.

Happy that my email was helpful in fixing your fundamental
misunderstanding of draft-fossati-tls-attestation-06 vs.
draft-fossati-seat-early-attestation-06. Apart from the README,
binder7 in Table 2 in the intra-handshake.fail paper clearly cites
[64] which is draft-fossati-tls-attestation-06. So could you please
narrowly answer my question: how did you conclude your statements
"draft-fossati-seat-early-attestation-06 was applied to binder 7" and
"README was updated to suggest that
draft-fossati-seat-early-attestation-06 is represented by what the
page labels as "binder 7""? If you can explain your rationale, maybe I
can help fix your remaining misunderstanding.

To clarify, I asked narrowly about your potential refusal of the
vulnerability CVE-2026-33697 because your position is unclear to me.
Thanks for pointing to the new draft version of
draft-intra-handshake-fail; paper's repo is pointing to older version
3. I see that ERISA has acknowledged it too by creating
EUVD-2026-16488
(https://www.ietf.org/archive/id/draft-intra-handshake-fail-04.html#section-3).
The section is an undeniable public evidence of the CVE. Clarifying
your position and rationale is helpful; it's fine to be the only one
refusing it. This will help me understand your previous email that I
was replying to.

My understanding is that `selfsign` is self-signed certificate for the
key generated within the TEE. Evidence cannot be transmitted as it is
in TLS 1.3, so a self-signed certificate is generated. Could you
clarify what sense it would make to check the self-signed certificate
at client-side? What needs to be checked before gate release is the
signature using AK and that is correctly there in my reading
(https://github.com/muhammad-usama-sardar/intra-handshake.fail/blob/819bb7f20ac458b27c9be2c91cce1e72b8b5f4f7/binder1/tls-lib-simple.pvl#L682).

I don't think it is helpful to downplay someone's work by calling it
"niaeve binders". Do you really believe that tall companies like Meta
are using what you call as "niaeve binders"? According to section 8 of
intra-handshake.fail paper, that has gone through "extensive security
review" (https://github.com/trailofbits/publications/blob/master/reviews/2025-08-meta-whatsapp-privateprocessing-securityreview.pdf)
by a cybersecurity firm "Trail of Bits". In my search, Trail of Bits
appears to be a very reputed firm. Do you really believe that a very
reputed cybersecurity firm missed "niaeve binders" in their "extensive
security review"?

Best,
Songbo