- Pod Affinity/AntiAffinity label selectors are now validated in the pod affinity score plugin ([#93758](https://github.com/kubernetes/kubernetes/pull/93758), [@damemi](https://github.com/damemi)) [SIG Scheduling]

    * To avoid that negative effect only use per pod metrics from pods that are:
    * - ready (so metrics about them should be valid), or
    * - unready but creation and last readiness change timestamps are apart more than 10s (pods that have formerly been ready and so metrics are in at least some cases (pod becoming unready because of overload) very useful).

For more information, see [#53040](https://github.com/kubernetes/kubernetes/issues/53040).

A security issue was discovered in Kubernetes where a user that can create pods and persistent volumes on Windows nodes may be able to escalate to admin privileges on those nodes. Kubernetes clusters are only affected if they are using an in-tree storage plugin for Windows nodes.

**Affected Versions**:
  - kubelet >= v1.8.0

**Fixed Versions**:
  - kubelet v1.28.4
  - kubelet v1.27.8
  - kubelet v1.26.11

*   NetworkPolicy objects are now stored in etcd in v1 format. After you upgrade to version 1.9, make sure that all NetworkPolicy objects are migrated to v1. ([#51955](https://github.com/kubernetes/kubernetes/pull/51955), [@danwinship](https://github.com/danwinship))

com/mtaufen))

* [GCP kube-up.sh] Variables that were part of kube-env that were only used for kubelet flags are no longer being set, and are being replaced by the more portable mechanism of the kubelet configuration file. The individual variables in the kube-env metadata entry were never meant to be a stable interface and this release note only applies if you are depending on them. ([#60020](https://github.com/kubernetes/kubernetes/pull/60020), [@roberthbailey](https://github.com/roberthbailey))...

* kubelets are no longer allowed to delete their own Node API object. Prior to 1.11, in rare circumstances related to cloudprovider node ID changes, kubelets would attempt to delete/recreate their Node object at startup. Kubelets older than 1.11 are not supported running against a v1.13+ API server. If an unsupported legacy kubelet encounters this situation, a cluster admin can...

* Pod priority and preemption is now enabled by default. Even if you don't plan to use this feature, you might need to take some action immediately after upgrading. In multi-tenant clusters where not all users are trusted, you are advised to create appropriate quotas for two default priority classes,...

* Third Party Resource tests in the e2e suite were incorrectly marked as part of the conformance bucket.  They are alpha and are not required for conformance. ([#52823](https://github.com/kubernetes/kubernetes/pull/52823), [@smarterclayton](https://github.com/smarterclayton))

With Kubernetes 1.15 as beta, OpenAPI schemas are also published for CRDs, as long as their schemas are structural.

These changes are reflected in the following Kubernetes enhancements: