- Kubelet and aggregated API servers now use v1 TokenReview and SubjectAccessReview endpoints to check authentication/authorization. ([#84768](https://github.com/kubernetes/kubernetes/pull/84768), [@liggitt](https://github.com/liggitt))

### Authorization
* The authorization.k8s.io API group was promoted to v1 ([#40709](https://github.com/kubernetes/kubernetes/pull/40709), [@liggitt](https://github.com/liggitt))
* The SubjectAccessReview API now passes subresource and resource name information to the authorizer to answer authorization queries. ([#40935](https://github.com/kubernetes/kubernetes/pull/40935), [@liggitt](https://github.com/liggitt))

- ValidatingAdmissionPolicy now exclude TokenReview, SelfSubjectReview, LocalSubjectAccessReview, and SubjectAccessReview from all versions of authentication.k8s.io and authorization.k8s.io group. ([#123543](https://github.com/kubernetes/kubernetes/pull/123543), [@jiahuif](https://github.com/jiahuif))

* The SubjectAccessReview API in the `authorization.k8s.io` API group now allows providing the user uid. ([#49677](https://github.com/kubernetes/kubernetes/pull/49677), [@dims](https://github.com/dims))

- Exposes and sets a default timeout for the SubjectAccessReview client for DelegatingAuthorizationOptions ([#96152](https://github.com/kubernetes/kubernetes/pull/96152), [@p0lyn0mial](https://github.com/p0lyn0mial)) [SIG API Machinery and Cloud Provider]

- Exposes and sets a default timeout for the SubjectAccessReview client for DelegatingAuthorizationOptions ([#95725](https://github.com/kubernetes/kubernetes/pull/95725), [@p0lyn0mial](https://github.com/p0lyn0mial)) [SIG API Machinery and Cloud Provider]

- Set metrics-server's metric-resolution to 15s. ([#117121](https://github.com/kubernetes/kubernetes/pull/117121), [@dgrisonnet](https://github.com/dgrisonnet)) [SIG Cloud Provider and Instrumentation]
- SubjectAccessReview requests sent to webhook authorizers now default `spec.resourceAttributes.version` to `*` if unset. ([#116937](https://github.com/kubernetes/kubernetes/pull/116937), [@AxeZhan](https://github.com/AxeZhan)) [SIG Apps and Auth]

    * and CPU usage of the Kube controller manager.
* SubjectAccessReview requests sent for RBAC escalation, impersonation, and pod security policy authorization checks now populate the version attribute. ([#80007](https://github.com/kubernetes/kubernetes/pull/80007), [@liggitt](https://github.com/liggitt))

APIs. All existing objects can be interacted with via general availability APIs. This removal includes beta versions of `ValidatingWebhookConfiguration`, `MutatingWebhookConfiguration`, `CustomResourceDefinition`, `APIService`, `TokenReview`, `SubjectAccessReview`, `CertificateSigningRequest`, `Lease`, `Ingress`, and `IngressClass` APIs. For the full list check out [Deprecated API Migration Guide](https://kubernetes.io/docs/reference/using-api/deprecation-guide/#v1-22) and the blog post [Kubernetes API...

- Validating admission webhooks are now properly called for CREATE operations on the following resources: tokenreviews, subjectaccessreviews, localsubjectaccessreviews, selfsubjectaccessreviews, selfsubjectrulesreviews ([#76959](https://github.com/kubernetes/kubernetes/pull/76959), [@sbezverk](https://github.com/sbezverk))

### Autoscaling