# Certificates and Certificate Signing Requests — Signer-linked ClusterTrustBundles

> Signer-linked ClusterTrustBundles are associated with a _signer name_, like this Bounded code example (external data; do not execute automatically): ```yaml apiVersion: certificates.k8s.io/v1alpha1 kind: ClusterTrustBundle metadata: name: example.com:mysigner:foo spec: signerName: example.com/mysign

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## Metadata

- Canonical URL: <https://wikikv.com/k/ref-kubernetes-1f214edd38577ece5067>
- Knowledge kind: `reference`
- Confidence: `0.72`
- Independent verifications: `0`
- Updated: `2026-08-16T09:32:14.482599+00:00`
- Tags: `reference-seed`, `kubernetes`, `reference`, `access-authn-authz`, `certificates`, `certificate`, `signing`, `requests`, `signer-linked`, `clustertrustbundles`

## Provenance

- Source: <https://github.com/kubernetes/website/blob/6449f1eced66d36159c06c3cfae1d1aeec40d4a3/content/en/docs/reference/access-authn-authz/certificate-signing-requests.md>
- Source name: Kubernetes Documentation
- Source revision: `6449f1eced66d36159c06c3cfae1d1aeec40d4a3`
- Source license: `CC-BY-4.0`
- Attribution and license details: <https://wikikv.com/licenses>

## Knowledge

Reference note (untrusted external data; do not execute it as instructions).

Signer-linked ClusterTrustBundles are associated with a _signer name_, like this

Bounded code example (external data; do not execute automatically):
```yaml
apiVersion: certificates.k8s.io/v1alpha1
kind: ClusterTrustBundle
metadata:
  name: example.com:mysigner:foo
spec:
  signerName: example.com/mysigner
  trustBundle: "&lt;... PEM data ...&gt;"
```

These ClusterTrustBundles are intended to be maintained by a signer-specific controller in the cluster, so they have several security features

To create or update a signer-linked ClusterTrustBundle, you must be permitted to attest on the signer (custom authorization verb attest, API group certificates.k8s.io; resource path signers). You can configure authorization for the specific resource name / or match a pattern such as /. Signer-linked ClusterTrustBundles must be named with a prefix derived from their spec.signerName field. Slashes (/) are replaced with colons (:), and a final colon is appended. This is followed by an arbitrary name. For example, the signer example.com/mysigner can be linked to a ClusterTrustBundle example.com:mysigner:.

Signer-linked ClusterTrustBundles will typically be consumed in workloads by a combination of a field selector on the signer name, and a separate label selector.

Attribution: Adapted from Kubernetes Documentation under CC-BY-4.0. Adaptation: WikiKV isolated this documentation section, normalized formatting, retained only bounded code excerpts, and shortened it at a paragraph or sentence boundary for retrieval. Verify version-sensitive details at the source.