[Discussion] Ballot SMC017v2: Increase Minimum RSA CA Key Size

[Stephen Davidson]

Ballot SMC017v2: Increase Minimum RSA CA Key Size

Summary: 

This ballot increases the minimum RSA key size for Root and Subordinate CA certificates in the S/MIME BRs from 2048 to 4096 bits for keys created after September 15, 2026, while retaining the 2048-bit minimum for Subscriber certificates.

The ballot further requires that by September 15, 2027, CAs SHALL NOT issue Subscriber certificates from any Sub-CA whose RSA key modulus is less than 3072 bits, effectively sunsetting issuance from legacy 2048-bit Sub-CAs.

The ballot also includes minor typographic corrections.

This ballot is proposed by Martijn Katerbarg (Sectigo) and endorsed by Ben Wilson (Mozilla) and Stephen Davidson (DigiCert)

— Motion Begins —

This ballot modifies the “Baseline Requirements for the Issuance and Management of Publicly-Trusted S/MIME Certificates” (“S/MIME Baseline Requirements”), based on Version 1.0.14.

MODIFY the Baseline Requirements as specified in the following Redline:

https://github.com/cabforum/smime/compare/3948f7f538133f6e9d731660f0fc36bfc8d98c13...ff477d9adb959f6b9c4318784267ed82232fedac

— Motion Ends —

This ballot proposes a Final Maintenance Guideline. The procedure for approval of this ballot is as follows:

Discussion (at least 7 days)

• Start time: June 16, 2026 at 18:00:00 UTC
• End time: June 23, 2026 at 18:00:00 UTC

[Stephen Davidson]

·         Start time: June 16, 2026 at 18:00:00 UTC

·         End time: June 23, 2026 at 18:00:00 UTC

Voting for Approval

·         Start time: June 23, 2026 at 18:00:00 UTC

·         End time: June 30, 2026 at 18:00:00 UTC

 

[Stefan Selbitschka]

rundQuadrat votes "yes" on SMC017v2

On 6/23/26 19:00, 'Stephen Davidson' via S/MIME Certificate WG - Public (CA/B Forum) wrote:
> *Ballot SMC017v2: Increase Minimum RSA CA Key Size*

>
> Summary:
>
> This ballot increases the minimum RSA key size for Root and Subordinate CA certificates in the S/
> MIME BRs from 2048 to 4096 bits for keys created after September 15, 2026, while retaining the 2048-
> bit minimum for Subscriber certificates.
>
> The ballot further requires that by September 15, 2027, CAs SHALL NOT issue Subscriber certificates
> from any Sub-CA whose RSA key modulus is less than 3072 bits, effectively sunsetting issuance from
> legacy 2048-bit Sub-CAs.
>
> The ballot also includes minor typographic corrections.
>
> This ballot is proposed by Martijn Katerbarg (Sectigo) and endorsed by Ben Wilson (Mozilla) and
> Stephen Davidson (DigiCert)
>
> — Motion Begins —
>
> This ballot modifies the “Baseline Requirements for the Issuance and Management of Publicly-Trusted
> S/MIME Certificates” (“S/MIME Baseline Requirements”), based on Version 1.0.14.
>
> MODIFY the Baseline Requirements as specified in the following Redline:
>
> https://github.com/cabforum/smime/
> compare/3948f7f538133f6e9d731660f0fc36bfc8d98c13...ff477d9adb959f6b9c4318784267ed82232fedac

> <https://url.avanan.click/v2/r01/___https:/github.com/cabforum/smime/
> compare/3948f7f538133f6e9d731660f0fc36bfc8d98c13...ff477d9adb959f6b9c4318784267ed82232fedac___.YXAzOmRpZ2ljZXJ0OmE6bzowMGFjNjE1ZDljZTk0NmE0Yjc0OTFiMTBmZGViMjgzYjo3OmRlN2M6YTkyNTVjZWEzZDBiZWNjZjUwNTYwNTNkMWExMTBhMTM4M2MzNTE4ODg0Zjc4NzI2YzI4ZmFhZDk0OTMyMWZhYzpoOlQ6Rg>

>
> — Motion Ends —
>
> This ballot proposes a Final Maintenance Guideline. The procedure for approval of this ballot is as
> follows:
>

> *Discussion *
>
> ·Start time: June 16, 2026 at 18:00:00 UTC

>
> ·End time: June 23, 2026 at 18:00:00 UTC
>

> *Voting for Approval *
>
> ·Start time: June 23, 2026 at 18:00:00 UTC

>
> ·End time: June 30, 2026 at 18:00:00 UTC
>

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[Adriano Santoni]

Actalis votes "yes" on SMC017v2.

Il 23/06/2026 19:00, 'Stephen Davidson' via S/MIME Certificate WG - Public (CA/B Forum) ha scritto:

External sender. Verify for authenticity before opening any links or attachments.

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[Michael Guenther]

[黃晟(orca)]

TWCA votes Yes on Ballot SMC017v2.

 

 

Best,

 

Sean Huang

Senior PKI Compliance Engineer
TEL：02-2370-8886#728
FAX：02-2388-6720
Email：or...@twca.com.tw

10F., No. 85, Yanping South Road,

Taipei, Taiwan (R.O.C.)

--

[Ben Wilson]

Mozilla votes "yes" on Ballot SMC-017v2.

--

[Dustin Hollenback]

Apple votes “yes" on Ballot SMC-017v2.

[Tim Hollebeek]

DigiCert votes “yes" on Ballot SMC-017v2.

-Tim

To view this discussion visit https://groups.google.com/a/groups.cabforum.org/d/msgid/smcwg-public/7A9AD2A5-898C-4360-A5BA-F559D549A0AC%40apple.com.

[Ashish Dhiman]

GlobalSign votes Yes to SMC017v2

Get Outlook for Android

---

From: 'Stephen Davidson' via S/MIME Certificate WG - Public (CA/B Forum) <smcwg-...@groups.cabforum.org>
Sent: Tuesday, June 23, 2026 10:31:08 pm
To: smcwg-...@groups.cabforum.org <smcwg-...@groups.cabforum.org>
Subject: [Smcwg-public] [Voting for Approval] Ballot SMC017v2: Increase Minimum RSA CA Key Size

--

[Nome Huang]

TrustAsia votes “Yes” on ballot SMC017v2.

[Ruiter, Albert de]

Logius votes “Yes” on ballot SMC017v2.

 

Kind regards,

Albert de Ruiter

Policy Authority PKIoverheid

 

Logius

 

Dienst Digitale Samenleving

Ministerie van Binnenlandse Zaken en Koninkrijksrelaties

........................................................................

M 06-22796535

Albert...@logius.nl

www.logius.nl

 

........................................................................

Logius is continu op zoek naar nieuwe collega’s. Bekijk alle vacatures op onze website.

Samen zorgen we voor een digitale overheid die werkt voor iedereen

--

[Scott Rea]

eMudhra Votes Yes to Ballot SMC017v2

From: 'Stephen Davidson' via S/MIME Certificate WG - Public (CA/B Forum) <smcwg-...@groups.cabforum.org>
Date: Tuesday, 23 June 2026 at 11:01 AM
To: smcwg-...@groups.cabforum.org <smcwg-...@groups.cabforum.org>

Subject: [Smcwg-public] [Voting for Approval] Ballot SMC017v2: Increase Minimum RSA CA Key Size

CAUTION: This email is originated from outside of the organization. Do not open the links or the attachments unless you recognize the sender and know the content is safe.

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[Inigo Barreira]

Sectigo votes yes

 

De: 'Stephen Davidson' via S/MIME Certificate WG - Public (CA/B Forum) <smcwg-...@groups.cabforum.org>
Enviado el: martes, 23 de junio de 2026 19:01
Para: smcwg-...@groups.cabforum.org
Asunto: [Smcwg-public] [Voting for Approval] Ballot SMC017v2: Increase Minimum RSA CA Key Size

 

Ballot SMC017v2: Increase Minimum RSA CA Key Size Summary: This ballot increases the minimum RSA key size for Root and Subordinate CA certificates in the S/MIME BRs from 2048 to 4096 bits for keys created after September 15, 2026, while retaining

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[Andrea Holland]

IdenTrust votes Yes to SMC-017v2

 

Sincerely,

Andrea Holland

--

[大野 文彰]

SECOM Trust Systems votes YES on Ballot SMC017v2.

 

Best regards,

 

ONO Fumiaki / 大野 文彰

(Japanese name order: family name first, in uppercase)

SECOM Trust Systems CO., LTD.

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[Dimitris Zacharopoulos (HARICA)]

HARICA votes "yes" to ballot SMC017v2.

--

[Pedro FUENTES]

OISTE Votes Yes to SMC017v2

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[Entschew, Enrico]

D-Trust votes „YES“ on Ballot SMC017v2.

 

Thanks,

Enrico

--

[Rebecca Kelley]

SSL.com votes "YES" on Ballot SMC017v2.

- Rebecca Kelley

[Karina Sirota Goodley]

Microsoft votes Yes on SMC017v2

[Kateryna Aleksieieva]

Certum votes YES on Ballot SMC017v2

 

Kind regards,

Kateryna Aleksieieva

From: 'Stephen Davidson' via S/MIME Certificate WG - Public (CA/B Forum) <smcwg-...@groups.cabforum.org>

Sent: Tuesday, June 23, 2026 7:01 PM
To: smcwg-...@groups.cabforum.org

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[Azira Zakaria]

MSC Trustgate votes YES on Ballot SMC017v2

 

 

Best regards,

Azira

 

From: 'Stephen Davidson' via S/MIME Certificate WG - Public (CA/B Forum) <smcwg-...@groups.cabforum.org>

Sent: Wednesday, 24 June, 2026 1:01 AM
To: smcwg-...@groups.cabforum.org

--

[Lahtiharju, Pekka]

Telia Company votes YES on Ballot SMC017v2

 

Best regards,

Pekka Lahtiharju

 

 

From: 'Stephen Davidson' via S/MIME Certificate WG - Public (CA/B Forum) <smcwg-...@groups.cabforum.org>

Sent: Tuesday, June 23, 2026 8:01 PM
To: smcwg-...@groups.cabforum.org

Subject: [Smcwg-public] [Voting for Approval] Ballot SMC017v2: Increase Minimum RSA CA Key Size

 

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[Stephen Davidson]

The voting period for Ballot SMC017v2: Increase Minimum RSA CA Key Size has completed. The ballot has: PASSED.

 

Voting Results

Certificate Issuers
17 votes in total:
 * 17 voting YES: Actalis S.p.A., Asseco Data Systems SA (Certum), DigiCert, D-TRUST, eMudhra, GlobalSign, HARICA, IdenTrust, MSC Trustgate Sdn Bhd, OISTE Foundation, SECOM Trust Systems, Sectigo, SSL.com, SwissSign, Telia Company, TrustAsia, TWCA
 * 0 voting NO:
 * 0 ABSTAIN:

Certificate Consumers
4 votes in total:
 * 4 voting YES: Apple, Microsoft, Mozilla, rundQuadrat
 * 0 voting NO:
 * 0 ABSTAIN:

 

Bylaws Requirements

1. Bylaw 2.3(6) requires:
 * In order for a ballot to be adopted by the Forum, two‐thirds (2/3) or more of the votes cast by the Voting Members in the Certificate Issuer category must be in favor of the ballot. This requirement was MET.
 * at least fifty percent (50%) plus one (1) of the votes cast by the Voting Members in the Certificate Consumer category must be in favor of the ballot. This requirement was MET.
 * At least one (1) Voting Member in each category must vote in favor of a ballot for the ballot to be adopted. This requirement was MET.

2. Bylaw 2.3(7) requires:
 * A ballot result will be considered valid only when more than half of the number of currently active Voting Members has participated. The number of currently active Voting Members is the average number of Voting Member organizations that have participated in the previous three (3) Forum Meetings and Forum Teleconferences.
  * the quorum was 10 for this ballot. This requirement was MET.

This ballot now enters the IP Rights Review Period to permit members to review the ballot for relevant IP rights issues. This will be notified in a separate email.

 

[Stephen Davidson]

# [IPR Review] Ballot SMC017v2: Increase Minimum RSA CA Key Size

 

This Review Notice is sent pursuant to Section 4.1 of the CA/Browser Forum’s Intellectual Property Rights Policy (v1.4). This Review Period of 30 days is for one Final Maintenance Guidelines. The complete draft Final Maintenance Guideline that is the subject of this Review Notice is attached.

 

### Summary of Review

 

Ballot for Review: Ballot SMC017v2: Increase Minimum RSA CA Key Size

 

Start of Review Period: 2026-06-30 20:00:00 UTC

End of Review Period: 2026-07-30 20:00:00 UTC

 

Members with any Essential Claim(s) to exclude must forward a written Notice to Exclude Essential Claims to the Working Group Chair (email to stephen.davidson at digicert.com) and also submit a copy to the CA/B Forum public mailing list (email to public at cabforum.org) before the end of the Review Period.

 

For details, please see the current version of the CA/Browser Forum Intellectual Property Rights Policy.

 

An optional template for submitting an Exclusion Notice is available at https://cabforum.org/wp-content/uploads/Template-for-Exclusion-Notice.pdf.

 

[Stephen Davidson]

As noted on the call today, due to mail delivery issues some votes were not counted despite having been made in the voting period and captured in the mail list records. This corrects that count.

 

The voting period for Ballot SMC017v2: Increase Minimum RSA CA Key Size has completed. The ballot has: PASSED.

 

Voting Results

Certificate Issuers
18 votes in total:
 * 18 voting YES: Actalis S.p.A., Asseco Data Systems SA (Certum), DigiCert, D-TRUST, eMudhra, GlobalSign, HARICA, IdenTrust, Logius PKIoverheid, MSC Trustgate Sdn Bhd, OISTE Foundation, SECOM Trust Systems, Sectigo, SSL.com, SwissSign, Telia Company, TrustAsia, TWCA

 * 0 voting NO:
 * 0 ABSTAIN:

Certificate Consumers
4 votes in total:
 * 4 voting YES: Apple, Microsoft, Mozilla, rundQuadrat
 * 0 voting NO:
 * 0 ABSTAIN: