Dear Mbed TLS Users,
We are preparing for a transition in the maintenance of TLS and X.509 libraries (both contained in the Mbed TLS project).
The existing maintainers will continue to develop and maintain TF-PSA-Crypto, which remains an actively maintained part of the project.
The existing maintainers will cease their involvement in their development and maintenance of Mbed TLS from April 2027.
Unless new maintainers have joined the project and ramped up by that time, security incident response, security fixes, and releases will cease from April 2027.
The future maintenance arrangements for the TLS and X.509 libraries have not yet been determined. We welcome contributions from organisations and individuals interested in helping sustain Mbed TLS, whether through engineering resources, funding, or other forms of support. The existing maintainers are committed to supporting new maintainers as they ramp up and take on responsibility for the libraries.
If you or your organisation are interested in contributing to the future maintenance of Mbed TLS, please contact mbed-tls-owner@lists.trustedfirmware.org.
We recognise the importance of these libraries to their users and the wider ecosystem, and hope that, with community involvement, a sustainable path forward can be established.
Kind regards, The Mbed TLS Team
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
That is quite disappointing. mbedTLS has been used as the crypto and TLS layer for Godot Engine for many years now, and we just updated to version 4 to match the release and support schedule. Knowing all that work was wasted, and we should have moved to a different library feels quite bad. It feels like this should have been communicated with the EoL announcement of version 3 instead of having users port to a version that's not in fact going been maintained any longer than the version 3 (contrary to what was communicated at the time).
Ciao, Fabio
On Thu, Oct 8, 2026, 20:32 Janos Follath via Mbed-tls-announce < mbed-tls-announce@lists.trustedfirmware.org> wrote:
Dear Mbed TLS Users,
We are preparing for a transition in the maintenance of TLS and X.509 libraries (both contained in the Mbed TLS project).
The existing maintainers will continue to develop and maintain TF-PSA-Crypto, which remains an actively maintained part of the project.
The existing maintainers will cease their involvement in their development and maintenance of Mbed TLS from April 2027.
Unless new maintainers have joined the project and ramped up by that time, security incident response, security fixes, and releases will cease from April 2027.
The future maintenance arrangements for the TLS and X.509 libraries have not yet been determined. We welcome contributions from organisations and individuals interested in helping sustain Mbed TLS, whether through engineering resources, funding, or other forms of support. The existing maintainers are committed to supporting new maintainers as they ramp up and take on responsibility for the libraries.
If you or your organisation are interested in contributing to the future maintenance of Mbed TLS, please contact mbed-tls-owner@lists.trustedfirmware.org.
We recognise the importance of these libraries to their users and the wider ecosystem, and hope that, with community involvement, a sustainable path forward can be established.
Kind regards, The Mbed TLS Team
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. -- Mbed-tls-announce mailing list -- mbed-tls-announce@lists.trustedfirmware.org To unsubscribe send an email to mbed-tls-announce-leave@lists.trustedfirmware.org
Hi Fabio,
Your disappointment is completely understandable. We communicated this change as early as we could, we weren’t aware that this was going to happen when we announced EoL of version 3.
All that work you have put into migrating is indeed at risk as things are today, but we are seeking support from the community and hoping that the continued maintenance of the project can be secured.
Best regards, Janos
From: Fabio Alessandrelli fabio.alessandrelli@gmail.com Date: Thursday, 8 October 2026 at 20:18 To: Janos Follath Janos.Follath@arm.com Cc: mbed-tls-announce@lists.trustedfirmware.org mbed-tls-announce@lists.trustedfirmware.org Subject: Re: [Mbed-tls-announce] Announcement: Future Maintenance of Mbed TLS
That is quite disappointing. mbedTLS has been used as the crypto and TLS layer for Godot Engine for many years now, and we just updated to version 4 to match the release and support schedule. Knowing all that work was wasted, and we should have moved to a different library feels quite bad. It feels like this should have been communicated with the EoL announcement of version 3 instead of having users port to a version that's not in fact going been maintained any longer than the version 3 (contrary to what was communicated at the time).
Ciao, Fabio
On Thu, Oct 8, 2026, 20:32 Janos Follath via Mbed-tls-announce <mbed-tls-announce@lists.trustedfirmware.orgmailto:mbed-tls-announce@lists.trustedfirmware.org> wrote: Dear Mbed TLS Users,
We are preparing for a transition in the maintenance of TLS and X.509 libraries (both contained in the Mbed TLS project).
The existing maintainers will continue to develop and maintain TF-PSA-Crypto, which remains an actively maintained part of the project.
The existing maintainers will cease their involvement in their development and maintenance of Mbed TLS from April 2027.
Unless new maintainers have joined the project and ramped up by that time, security incident response, security fixes, and releases will cease from April 2027.
The future maintenance arrangements for the TLS and X.509 libraries have not yet been determined. We welcome contributions from organisations and individuals interested in helping sustain Mbed TLS, whether through engineering resources, funding, or other forms of support. The existing maintainers are committed to supporting new maintainers as they ramp up and take on responsibility for the libraries.
If you or your organisation are interested in contributing to the future maintenance of Mbed TLS, please contact mbed-tls-owner@lists.trustedfirmware.orgmailto:mbed-tls-owner@lists.trustedfirmware.org.
We recognise the importance of these libraries to their users and the wider ecosystem, and hope that, with community involvement, a sustainable path forward can be established.
Kind regards, The Mbed TLS Team
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. -- Mbed-tls-announce mailing list -- mbed-tls-announce@lists.trustedfirmware.orgmailto:mbed-tls-announce@lists.trustedfirmware.org To unsubscribe send an email to mbed-tls-announce-leave@lists.trustedfirmware.orgmailto:mbed-tls-announce-leave@lists.trustedfirmware.org IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
Dear Mbed TLS Team,
Thank you for the announcement and for the work that has gone into maintaining Mbed TLS over the years.
Given that the maintenance of the TLS and X.509 libraries is currently uncertain beyond April 2027, I would like to ask for your recommendation regarding new projects.
Should Mbed TLS still be considered a recommended choice for new designs starting today, or would you advise organizations to evaluate alternative TLS stacks until the long-term maintenance situation becomes clearer?
I believe guidance from the maintainers on this point would be very valuable for companies making technology decisions with product lifecycles extending well beyond 2027.
Thank you in advance for your clarification.
Kind regards, Massimiliano Cialdi
Massimiliano Cialdi FIRMWARE ENGINEERING PROFESSIONAL LEADER
Powersoft S.p.A. Via E. Conti, 5 - Scandicci (FI) 50018 - Italy OFFICE: +39 055 7350230 [cid:2_3b23bc2c-3db3-4330-b6f5-3fb62b89422a.png]https://www.facebook.com/powersoft/[cid:3_7da2eb67-7c7f-41e6-9598-128bdd52ec04.png]https://www.instagram.com/powersoft.official/[cid:4_a5d469e7-3228-4fb1-948d-4c3e879ea0da.png]https://www.youtube.com/@powersoftaudio[cid:5_e4390674-51fd-4219-9389-28ae9a12796d.png]https://www.linkedin.com/company/powersoft[cid:6_083a55f9-076c-4d52-9f93-69225b28cb32.png]https://open.spotify.com/show/6lwXROYcCyrVnJi6J9fA42[cid:7_7fd8585e-63fd-441a-95f3-6c0b23d059e1.png]https://x.com/Powersoft_Japan[cid:8_6308aaa9-b97d-405b-a86c-0300a381d13f.png]https://space.bilibili.com/3546387314641333[cid:9_9af1e42f-0019-42c4-8046-d6246e65ed9e.png]https://teams.microsoft.com/l/chat/0/0?users=massimiliano.cialdi@powersoft.com
[cid:pwsrgbn_12214209-f50f-45fa-be18-2a4cf1a5818a.png]https://www.powersoft.com/en
________________________________ From: Janos Follath via Mbed-tls-announce via mbed-tls mbed-tls@lists.trustedfirmware.org Sent: Thursday, 8 October 2026 20:31 To: mbed-tls-announce@lists.trustedfirmware.org mbed-tls-announce@lists.trustedfirmware.org Subject: [mbed-tls] [Mbed-tls-announce] Announcement: Future Maintenance of Mbed TLS
Dear Mbed TLS Users,
We are preparing for a transition in the maintenance of TLS and X.509 libraries (both contained in the Mbed TLS project).
The existing maintainers will continue to develop and maintain TF-PSA-Crypto, which remains an actively maintained part of the project.
The existing maintainers will cease their involvement in their development and maintenance of Mbed TLS from April 2027.
Unless new maintainers have joined the project and ramped up by that time, security incident response, security fixes, and releases will cease from April 2027.
The future maintenance arrangements for the TLS and X.509 libraries have not yet been determined. We welcome contributions from organisations and individuals interested in helping sustain Mbed TLS, whether through engineering resources, funding, or other forms of support. The existing maintainers are committed to supporting new maintainers as they ramp up and take on responsibility for the libraries.
If you or your organisation are interested in contributing to the future maintenance of Mbed TLS, please contact mbed-tls-owner@lists.trustedfirmware.org.
We recognise the importance of these libraries to their users and the wider ecosystem, and hope that, with community involvement, a sustainable path forward can be established.
Kind regards, The Mbed TLS Team
Dear Massimiliano,
We are seeking support from the community and hoping that the continued maintenance of the project can be secured. That said, your assessment is correct the maintenance of the TLS and X.509 libraries is uncertain at this point.
My recommendation for new projects would be to evaluate alternative TLS stacks and choose the one that is best for them even if Mbed TLS maintenance would be certain. (Mbed TLS is a very good TLS library, but not a panacea: it is optimal for some use cases sub-optimal for others.) However, I appreciate that the current situation makes this evaluation even more difficult.
If I had to start a project today, I would give a chance to Mbed TLS with some contingency planning. But please don’t take this as a recommendation, because as a developer of Mbed TLS I am inherently biased and it is very difficult for me to be impartial.
Kind regards, Janos
From: Massimiliano Cialdi via mbed-tls mbed-tls@lists.trustedfirmware.org Date: Friday, 9 October 2026 at 07:43 To: Gilles Peskine via mbed-tls mbed-tls@lists.trustedfirmware.org Subject: [mbed-tls] Re: Announcement: Future Maintenance of Mbed TLS
Dear Mbed TLS Team,
Thank you for the announcement and for the work that has gone into maintaining Mbed TLS over the years.
Given that the maintenance of the TLS and X.509 libraries is currently uncertain beyond April 2027, I would like to ask for your recommendation regarding new projects.
Should Mbed TLS still be considered a recommended choice for new designs starting today, or would you advise organizations to evaluate alternative TLS stacks until the long-term maintenance situation becomes clearer?
I believe guidance from the maintainers on this point would be very valuable for companies making technology decisions with product lifecycles extending well beyond 2027.
Thank you in advance for your clarification.
Kind regards, Massimiliano Cialdi
Massimiliano Cialdi FIRMWARE ENGINEERING PROFESSIONAL LEADER
Powersoft S.p.A. Via E. Conti, 5 - Scandicci (FI) 50018 - Italy OFFICE: +39 055 7350230 [2.png]https://www.facebook.com/powersoft/[3.png]https://www.instagram.com/powersoft.official/[4.png]https://www.youtube.com/@powersoftaudio[5.png]https://www.linkedin.com/company/powersoft[6.png]https://open.spotify.com/show/6lwXROYcCyrVnJi6J9fA42[7.png]https://x.com/Powersoft_Japan[8.png]https://space.bilibili.com/3546387314641333[9.png]https://teams.microsoft.com/l/chat/0/0?users=massimiliano.cialdi@powersoft.com
[PWS rgb N.png]https://www.powersoft.com/en
________________________________ From: Janos Follath via Mbed-tls-announce via mbed-tls mbed-tls@lists.trustedfirmware.org Sent: Thursday, 8 October 2026 20:31 To: mbed-tls-announce@lists.trustedfirmware.org mbed-tls-announce@lists.trustedfirmware.org Subject: [mbed-tls] [Mbed-tls-announce] Announcement: Future Maintenance of Mbed TLS
Dear Mbed TLS Users,
We are preparing for a transition in the maintenance of TLS and X.509 libraries (both contained in the Mbed TLS project).
The existing maintainers will continue to develop and maintain TF-PSA-Crypto, which remains an actively maintained part of the project.
The existing maintainers will cease their involvement in their development and maintenance of Mbed TLS from April 2027.
Unless new maintainers have joined the project and ramped up by that time, security incident response, security fixes, and releases will cease from April 2027.
The future maintenance arrangements for the TLS and X.509 libraries have not yet been determined. We welcome contributions from organisations and individuals interested in helping sustain Mbed TLS, whether through engineering resources, funding, or other forms of support. The existing maintainers are committed to supporting new maintainers as they ramp up and take on responsibility for the libraries.
If you or your organisation are interested in contributing to the future maintenance of Mbed TLS, please contact mbed-tls-owner@lists.trustedfirmware.org.
We recognise the importance of these libraries to their users and the wider ecosystem, and hope that, with community involvement, a sustainable path forward can be established.
Kind regards, The Mbed TLS Team
Hi Janos,
Thanks for making us aware, and also for all your work.
I would try to be sure. Does this actually imply "https://github.com/Mbed-TLS/mbedtls" ? If so, what would it mean for existing Pull Requests which are created for mbedtls?
Thanks & Regards,
* Nayna
________________________________ From: Janos Follath via Mbed-tls-announce via mbed-tls mbed-tls@lists.trustedfirmware.org Sent: Thursday, October 8, 2026 2:31 PM To: mbed-tls-announce@lists.trustedfirmware.org mbed-tls-announce@lists.trustedfirmware.org Subject: [EXTERNAL] [mbed-tls] [Mbed-tls-announce] Announcement: Future Maintenance of Mbed TLS
Dear Mbed TLS Users,
We are preparing for a transition in the maintenance of TLS and X.509 libraries (both contained in the Mbed TLS project).
The existing maintainers will continue to develop and maintain TF-PSA-Crypto, which remains an actively maintained part of the project.
The existing maintainers will cease their involvement in their development and maintenance of Mbed TLS from April 2027.
Unless new maintainers have joined the project and ramped up by that time, security incident response, security fixes, and releases will cease from April 2027.
The future maintenance arrangements for the TLS and X.509 libraries have not yet been determined. We welcome contributions from organisations and individuals interested in helping sustain Mbed TLS, whether through engineering resources, funding, or other forms of support. The existing maintainers are committed to supporting new maintainers as they ramp up and take on responsibility for the libraries.
If you or your organisation are interested in contributing to the future maintenance of Mbed TLS, please contact mbed-tls-owner@lists.trustedfirmware.org.
We recognise the importance of these libraries to their users and the wider ecosystem, and hope that, with community involvement, a sustainable path forward can be established.
Kind regards, The Mbed TLS Team
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. -- Mbed-tls-announce mailing list -- mbed-tls-announce@lists.trustedfirmware.org To unsubscribe send an email to mbed-tls-announce-leave@lists.trustedfirmware.org -- mbed-tls mailing list -- mbed-tls@lists.trustedfirmware.org To unsubscribe send an email to mbed-tls-leave@lists.trustedfirmware.org
Hi Nayna,
Yes, the announcement is about https://github.com/Mbed-TLS/mbedtls. The pull requests that are not merged before April will remain there. The new maintainer team can pick them up if and when they are established.
Best regards, Janos
From: NAYNA JAIN naynjain@ibm.com Date: Friday, 9 October 2026 at 12:38 To: mbed-tls-announce@lists.trustedfirmware.org mbed-tls-announce@lists.trustedfirmware.org; Janos Follath Janos.Follath@arm.com Subject: Re: Announcement: Future Maintenance of Mbed TLS
Hi Janos,
Thanks for making us aware, and also for all your work.
I would try to be sure. Does this actually imply "https://github.com/Mbed-TLS/mbedtls" ? If so, what would it mean for existing Pull Requests which are created for mbedtls?
Thanks & Regards,
* Nayna
________________________________ From: Janos Follath via Mbed-tls-announce via mbed-tls mbed-tls@lists.trustedfirmware.org Sent: Thursday, October 8, 2026 2:31 PM To: mbed-tls-announce@lists.trustedfirmware.org mbed-tls-announce@lists.trustedfirmware.org Subject: [EXTERNAL] [mbed-tls] [Mbed-tls-announce] Announcement: Future Maintenance of Mbed TLS
Dear Mbed TLS Users,
We are preparing for a transition in the maintenance of TLS and X.509 libraries (both contained in the Mbed TLS project).
The existing maintainers will continue to develop and maintain TF-PSA-Crypto, which remains an actively maintained part of the project.
The existing maintainers will cease their involvement in their development and maintenance of Mbed TLS from April 2027.
Unless new maintainers have joined the project and ramped up by that time, security incident response, security fixes, and releases will cease from April 2027.
The future maintenance arrangements for the TLS and X.509 libraries have not yet been determined. We welcome contributions from organisations and individuals interested in helping sustain Mbed TLS, whether through engineering resources, funding, or other forms of support. The existing maintainers are committed to supporting new maintainers as they ramp up and take on responsibility for the libraries.
If you or your organisation are interested in contributing to the future maintenance of Mbed TLS, please contact mbed-tls-owner@lists.trustedfirmware.org.
We recognise the importance of these libraries to their users and the wider ecosystem, and hope that, with community involvement, a sustainable path forward can be established.
Kind regards, The Mbed TLS Team
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. -- Mbed-tls-announce mailing list -- mbed-tls-announce@lists.trustedfirmware.org To unsubscribe send an email to mbed-tls-announce-leave@lists.trustedfirmware.org -- mbed-tls mailing list -- mbed-tls@lists.trustedfirmware.org To unsubscribe send an email to mbed-tls-leave@lists.trustedfirmware.org IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
Hello,
Like other community members, we are regretting that Mbed TLS 4.x was initially announced as supported until March 2029 (which is still currently the case at https://github.com/Mbed-TLS/mbedtls/blob/development/BRANCHES.md#current-bra...).
In our company, we are depending on Mbed TLS for multiple products, and are currently discussing internally about our best strategy forward given this announcement, with multiple possibilities: - switching to another TLS library; - discussing with partners to help sustain the X.509 and TLS libraries of Mbed TLS.
We encourage other members of the community interested in sustaining Mbed TLS to make themselves known.
Best regards,
Paul Lajoie-Mazenc Schneider Electric ________________________________ De : Janos Follath via Mbed-tls-announce via mbed-tls mbed-tls@lists.trustedfirmware.org Envoyé : jeudi 8 octobre 2026 20:31 À : mbed-tls-announce@lists.trustedfirmware.org mbed-tls-announce@lists.trustedfirmware.org Objet : [mbed-tls] [Mbed-tls-announce] Announcement: Future Maintenance of Mbed TLS
[External email: Use caution with links and attachments]
________________________________
Dear Mbed TLS Users,
We are preparing for a transition in the maintenance of TLS and X.509 libraries (both contained in the Mbed TLS project).
The existing maintainers will continue to develop and maintain TF-PSA-Crypto, which remains an actively maintained part of the project.
The existing maintainers will cease their involvement in their development and maintenance of Mbed TLS from April 2027.
Unless new maintainers have joined the project and ramped up by that time, security incident response, security fixes, and releases will cease from April 2027.
The future maintenance arrangements for the TLS and X.509 libraries have not yet been determined. We welcome contributions from organisations and individuals interested in helping sustain Mbed TLS, whether through engineering resources, funding, or other forms of support. The existing maintainers are committed to supporting new maintainers as they ramp up and take on responsibility for the libraries.
If you or your organisation are interested in contributing to the future maintenance of Mbed TLS, please contact mbed-tls-owner@lists.trustedfirmware.org.
We recognise the importance of these libraries to their users and the wider ecosystem, and hope that, with community involvement, a sustainable path forward can be established.
Kind regards, The Mbed TLS Team
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. -- Mbed-tls-announce mailing list -- mbed-tls-announce@lists.trustedfirmware.org To unsubscribe send an email to mbed-tls-announce-leave@lists.trustedfirmware.org -- mbed-tls mailing list -- mbed-tls@lists.trustedfirmware.org To unsubscribe send an email to mbed-tls-leave@lists.trustedfirmware.org
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NAYNA JAIN via Mbed-tls-announce
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