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2025-05-07 Minutes of the S/MIME Certificate Working Group

Minutes of SMCWG

May 7, 2025

These are the Minutes of the meeting described in the subject of this message. Corrections and clarifications where needed are encouraged by reply.


1. Note Well and Antitrust Statement


2. Roll Call

  • Taken from recording (Webex). See “Attendees” below.

3. Approval of Prior Minutes

  • Minutes from April 23 were approved.
  • Minutes were taken by Stephen Davidson.

4. Agenda Review

  • The agenda was reviewed. There were no additions.

5. Membership Applications

  • None

6. Discussion Topics

* Topic 1: SMC012 ACME for S/MIME

Stephen Davidson noted that a ballot was ready to go after SMC011 IPR concludes on May 14. It will include the correction for directoryName in SAN previously discussed. Stephen asked the group to make a final review, and the WG walked through the proposed text.

Andy Warner suggested that language might be added to allow a reuse period for mail domain control validations performed using ACME. Guillaume Amringer noted that a DNS pre-authorization using the TLS methods already allowed a reuse period.

https://github.com/srdavidson/smime/compare/c80922087427b1368cb8991eaad4128ef8fe52c0...46f48f891743860a8ab30e8c8f0985bfe22c8d57

Stephen noted the SMCWG welcomes proposals to improve automation possibilities via the S/MIME BR.

* Topic 2: Pseudonym readiness for ballot?

The WG reviewed the proposed text and debated whether the language should step up to require the prefix after an implementation period. Adrian Mueller noted that Outlook defaults to display the CN, so tagging the Pseudonym prevented the chance for confusion. Martijn Katerbarg supported that. Clint Wilson said he preferred consistency if the prefix were to be allowed. Andreas Henschel said that in Germany in the past sometimes the PN: was used as a suffix (i.e., after the name).

Stephen noted that theoretically you could use an email address in the Pseudonym and there were no requirements to validate it, which could create confusion.

https://github.com/srdavidson/smime/compare/c80922087427b1368cb8991eaad4128ef8fe52c0...3fb02751100f9d0dd366d2b48ec5e544fc5b1939

* Topic 3: PQC, what else is needed for ballot? https://github.com/cabforum/smime/issues/280

The WG reviewed the proposed text. Stephen asked for assistance in reviewing it and asked if additional guardrails should be added. He asked if a note should be added to explain that PQC was added to allow experimentation but that additional root program rules may apply. The WG discussed if rules needed to be stated for what type of CA can sign what type of certificate; it was agreed that the current S/MIME BR Section 7 did not have the same degree of specification in this regard as re TLS BR. Stephen noted that the WG should probably consider a change to the Section 7 format for consistency across the CABF standards, and to accommodate the growing number of algorithms and cert types that will need to be supported.

* Topic 4: Coming up

Stephen asked if there were volunteers willing to assist in drafting an update to section 7 to adopt the more detailed approach now used in the TLS BR. Clint Wilson and Andy Warner said they’d be willing to help.


7. Ballot Status Updates (if applicable)

  • Upcoming Drafts / In Development: SMC012 – ACME For S/MIME
  • In Discussion Period: NA
  • In Voting Period: NA
  • Under IPR Review: SMC011 until May 14, 2025
  • Approved and Effective: NA

8. Next Meeting

Date: Wednesday, May 21 2025 at 11:00 am Eastern Time


9. Any Other Business

  • None

10. Adjournment

  • The meeting was adjourned.

11. Attendees

Adrian Mueller (SwissSign), Andreas Henschel (D-TRUST), Andy Warner (Google), Ashish Dhiman (GlobalSign), Bruce Morton (Entrust), Clint Wilson (Apple), Guillaume Amringer (Carillon Information Security Inc.), Hazhar Ismail (MSC Trustgate Sdn Bhd), Inaba Atsushi (GlobalSign), Iñigo Barreira (Sectigo), Judith Spencer (CertiPath), Lilia Dubko (CPA Canada/WebTrust), Malcolm Idaho (IdenTrust), Martijn Katerbarg (Sectigo), Nargis Mannan (VikingCloud), Nome Huang (TrustAsia), Ono Fumiaki (SECOM Trust Systems), Patrycja Schrenk (PSW), Pekka Lahtiharju (Telia Company), Peter Miskovic (Disig), Rollin Yu (TrustAsia), Russ Housley (Vigil Security LLC), Scott Rea (eMudhra), Stefan Selbitschka (rundQuadrat), Stephen Davidson (DigiCert), Tadahiko Ito (SECOM Trust Systems), Thomas Zermeno (SSL.com), Tim Hollebeek (DigiCert), Tsung-Min Kuo (Chunghwa Telecom), Zurina Zolkaffly (MSC Trustgate Sdn Bhd)

Latest releases
Server Certificate Requirements
SC-081v3: Introduce Schedule of Reducing Validity and Data Reuse Periods - May 21, 2025

BR v2.1.5

Code Signing Requirements
v3.8 - Aug 5, 2024

What’s Changed CSC-25: Import EV Guidelines to CS Baseline Requirements by @dzacharo in https://github.com/cabforum/code-signing/pull/38 Full Changelog: https://github.com/cabforum/code-signing/compare/v3.7...v3.8

S/MIME Requirements
v1.0.9 - Ballot SMC011 - May 14, 2025

This ballot allows the option to use a European Unique Identifier (EUID) as a Registration Reference in the NTR Registration Scheme. The EUID uniquely identifies officially-registered organizations, Legal Entities, and branch offices within the European Union or the European Economic Area. The EUID is specified in chapter 9 of the Annex contained in the Implementing Regulation (EU) 2021/1042 which describes rules for the application of Directive (EU) 2017/1132 “relating to certain aspects of company law (codification)”. The ballot also includes several editorial corrections, (e.g., reordering of References and regrouping of information from Appendix A to Section 7.1.4.2.2 (d)). This ballot is proposed by Stephen Davidson (DigiCert) and endorsed by Adrian Mueller (SwissSign) and Adriano Santoni (Actalis).

Network and Certificate System Security Requirements
v2.0 - Ballot NS-003 - Jun 26, 2024

Ballot NS-003: Restructure the NCSSRs in https://github.com/cabforum/netsec/pull/35

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