Release 1.21

cert-manager v1.21 includes:

• Removal of the default tokenrequest RBAC from the Helm chart (breaking change)

Major Themes

Default tokenrequest RBAC removed from Helm chart

⚠️ Breaking change

The Helm chart no longer creates a default Role and RoleBinding granting the cert-manager controller permission to create tokens for its own ServiceAccount (serviceaccounts/token: create).

This RBAC was added in v1.16 (cert-manager/cert-manager#7213) to support a "Using the cert-manager ServiceAccount" section in the Route53 documentation. That docs section was subsequently removed (cert-manager/website#1555) when the Route53 page was restructured, and no documented workflow — Route53 IRSA ambient, Vault Kubernetes auth, or any other issuer — requires the controller to mint tokens for its own ServiceAccount.

If you use serviceAccountRef.name pointing at the controller ServiceAccount, you must now either:

• create your own Role and RoleBinding granting serviceaccounts/token: create on that ServiceAccount, or
• migrate to a dedicated ServiceAccount with its own RBAC (recommended — see the Vault or Route53 documentation).

Credit to @everping and @kodareef5 for independently identifying (via privately reported security advisories) that this default RBAC widened the trust boundary beyond what cert-manager's published threat model documents.

Skip the self-check with waitInsteadOfSelfCheck

cert-manager 1.21 adds the waitInsteadOfSelfCheck solver option for ACME HTTP01 and DNS01 challenges. When set, cert-manager skips its own self-check and instead waits the configured duration after presentation before asking the ACME server to validate. This is an escape hatch for environments where cert-manager cannot reliably observe the same validation path as the ACME server, such as split-horizon DNS or NAT loopback (or hairpinning).

See Skip the self-check with waitInsteadOfSelfCheck for configuration details.

Webhook Serving Certificate Renewal After System Suspend

The cert-manager webhook generates and automatically renews its own self-signed serving certificate. Prior to 1.21, the renewal timer relied solely on Go's monotonic clock (CLOCK_MONOTONIC). During system suspend (S3/S4) or VM live migration, CLOCK_MONOTONIC stops advancing while wall-clock time (CLOCK_REALTIME) continues. When the system resumes, the renewal timer has not yet reached its deadline, so the webhook's serving certificate is never renewed — even though it has already expired. This causes x509: certificate has expired or is not yet valid errors for all admission and conversion webhook calls.

cert-manager 1.21 adds a periodic ticker that polls wall-clock time against the renewal deadline, detecting missed renewals regardless of whether CLOCK_MONOTONIC advanced. The webhook now recovers within one minute of system resume.

More details are available in the PR: https://github.com/cert-manager/cert-manager/pull/8464.

Community

As always, we'd like to thank all of the community members who helped in this release cycle, including all below who merged a PR and anyone that helped by commenting on issues, testing, or getting involved in cert-manager meetings. We're lucky to have you involved.

A special thanks to:

• TODO

for their contributions, comments and support!

Also, thanks to the cert-manager maintainer team for their help in this release:

• @inteon
• @erikgb
• @SgtCoDFish
• @ThatsMrTalbot
• @munnerz
• @maelvls

And finally, thanks to the cert-manager steering committee for their feedback in this release cycle:

• @FlorianLiebhart
• @ssyno
• @ianarsenault
• @TrilokGeer

v1.21.0

Feature

• Add the waitInsteadOfSelfCheck solver option for ACME HTTP01 and DNS01 challenges, allowing cert-manager to skip its own self-check and ask the ACME server to validate after a configured wait. See the ACME issuer documentation for configuration details.

Documentation

TODO

Bug or Regression

• Fix webhook serving certificate not being renewed after system suspend or VM live migration. (#8464, @Peac36)

Other (Cleanup or Flake)

• Removed the default tokenrequest Role and RoleBinding from the Helm chart that granted the controller ServiceAccount permission to mint tokens for itself. No documented workflow requires this RBAC. Users who relied on the undocumented pattern of pointing serviceAccountRef.name at the controller ServiceAccount must create their own Role and RoleBinding, or migrate to a dedicated ServiceAccount. See the upgrading notes for details. (cert-manager/cert-manager#8931, @wallrj-cyberark)