[CFRG] RG Last Call on draft-irtf-cfrg-hybrid-kems-12 and draft-irtf-cfrg-concrete-hybrid-kems-04

[Nick Sullivan <[e-mail]>]

Dear CFRG,

This message starts a two-week RG Last Call on two related documents. The
last
call ends on Wednesday July 22, 2026:

  Hybrid PQ/T Key Encapsulation Mechanisms (generic constructions)
  draft-irtf-cfrg-hybrid-kems-12
  https://www.ietf.org/archive/id/draft-irtf-cfrg-hybrid-kems-12.html

  Concrete Hybrid PQ/T Key Encapsulation Mechanisms
  draft-irtf-cfrg-concrete-hybrid-kems-04

https://www.ietf.org/archive/id/draft-irtf-cfrg-concrete-hybrid-kems-04.html

Both are intended as Informational RFCs. Please reply on-list with your
position
on each document: ready to publish as-is, ready with specific changes, or
not
ready, together with the technical reasons. This feedback will help the
chairs
judge whether the documents are ready for IRSG review and publication.

The scope and approach of this work were settled when the group adopted it
well
over a year ago, and both drafts have developed on the list in the open
since
then. This last call is about whether the text is technically correct and
complete, so please ground any objection in a specific problem with the
documents. Detailed comments are best filed as issues on the repositories
(https://github.com/cfrg/draft-irtf-cfrg-hybrid-kems,
https://github.com/cfrg/draft-irtf-cfrg-concrete-hybrid-kems) positions
belong
here on the list.

Both documents were reviewed by the CFRG Crypto Review Panel ahead of this
last
call. The reviews are on the CFRG and crypto-panel lists:

  Thomas Pornin (NCC Group), 3 June 2026, reviewed the generic framework
with a
  focus on the constructions and reductions, and concluded that it
describes a
  secure construction, with editorial and technical comments now reflected
in -12.

  Virendra Kumar (Qualcomm), 8 June 2026, reviewed the generic framework for
  clarity, with notational comments now reflected in -12.

  Russ Housley (Vigil Security), 2 June 2026, reviewed both drafts and
found the
  constructions and instantiations as specified.

The current revisions incorporate changes proposed by the panel's comments.

Thank you,
Nick, for the CFRG chairs