### Bug or Regression

- Fix an ephemeral port exhaustion bug caused by improper connection management that occurred when a large number of objects were handled by kubectl while exec auth was in use. ([#112337](https://github.com/kubernetes/kubernetes/pull/112337), [@enj](https://github.com/enj)) [SIG API Machinery and Auth]

* Fix for Pod stuck in ContainerCreating with error "Volume is not yet attached according to node". ([#50806](https://github.com/kubernetes/kubernetes/pull/50806), [@verult](https://github.com/verult))
* Fix initial exec terminal dimensions. ([#51126](https://github.com/kubernetes/kubernetes/pull/51126), [@chen-anders](https://github.com/chen-anders))

This release also contains a number of bug fixes to the feature set. Aspiring plugin authors can look at [sample-exec-plugin](https://github.com/ankeesler/sample-exec-plugin) as a way to get started.

## Urgent Upgrade Notes 

### (No, really, you MUST read this before you upgrade)

### Other (Cleanup or Flake)

- "Removed the ability to run `kubectl exec [POD] [COMMAND]` without a `--` separator.
  The `--` separator has been recommended since the Kubernetes v1.18 release, which also deprecated the legacy way of invoking `kubectl exec`.
  

kubernetes/kubernetes/pull/58973), [@verb](https://github.com/verb))

* The default Flexvolume plugin directory for COS images on GCE has changed to `/home/kubernetes/flexvolume`, rather than `/etc/srv/kubernetes/kubelet-plugins/volume/exec`. Existing Flexvolume installations in clusters using COS images must be moved to the new directory, and installation processes must be updated with the new path. ([#58171](https://github.com/kubernetes/kubernetes/pull/58171), [@verult](https://github.com/verult))...

* The priorityClass feature is now considered beta. ([#63724](https://github.com/kubernetes/kubernetes/pull/63724), [@ravisantoshgudimetla](https://github.com/ravisantoshgudimetla))
* client-go: credential exec plugins is now considered beta. ([#64482](https://github.com/kubernetes/kubernetes/pull/64482), [@ericchiang](https://github.com/ericchiang))

- The `--pod` flag (`-p` shorthand) of the kubectl exec command has been marked as deprecated, and will be removed in a future version. This flag is currently optional. ([#66558](https://github.com/kubernetes/kubernetes/pull/66558), [@quasoft](https://github.com/quasoft))

* CRI: Add stdout/stderr fields to Exec and Attach requests. ([#52686](https://github.com/kubernetes/kubernetes/pull/52686), [@yujuhong](https://github.com/yujuhong))
* Cluster Autoscaler 1.0.0 ([#53005](https://github.com/kubernetes/kubernetes/pull/53005), [@mwielgus](https://github.com/mwielgus))

- Changed the error message to `cannot exec into multiple objects at a time` when file passed to `kubectl exec` contains multiple resources ([#114249](https://github.com/kubernetes/kubernetes/pull/114249), [@ardaguclu](https://github.com/ardaguclu))