- kube-apiserver:

- Adds feature gate `KubeletInUserNamespace` which enables support for running kubelet in a user namespace.
  
  The user namespace has to be created before running kubelet.
  All the node components such as CRI need to be running in the same user namespace.
  

* [beta] SelfSubjectRulesReview, an API that lets a user see what actions they can perform with a namespace, has been added to the authorization.k8s.io API group. This bulk query is intended to enable UIs to show/hide actions based on the end user, and for users to quickly reason about their own permissions.

- In order to enable dual-stack support within kubeadm and kubernetes components, as part of the init config file, the user should set feature-gate `IPv6DualStack=true` in the ClusterConfiguration. Additionally, for each worker node, the user should set the feature-gate for kubelet using either `nodeRegistration.kubeletExtraArgs` or `KUBELET_EXTRA_ARGS`. ([#80531](https://github.com/kubernetes/kubernetes/pull/80531), [@Arvinder...

   1. Currently, if users were to explicitly specify CacheSize of 0 for KMS provider, they would end-up with a provider that caches up to 1000 keys. This PR changes this behavior.
      Post this PR, when users supply 0 for CacheSize this will result in a validation error.
   2. CacheSize type was changed from int32 to *int32. This allows defaulting logic to differentiate between cases where users explicitly supplied 0 vs. not supplied any value.

    * Switch default storage backend flag in apiserver to `etcd3` mode.

This release contains changes that address the following vulnerabilities:

### CVE-2024-3177: Bypassing mountable secrets policy imposed by the ServiceAccount admission plugin

A security issue was discovered in Kubernetes where users may be able to launch containers that bypass the mountable secrets policy enforced by the ServiceAccount admission plugin when using containers, init containers, and ephemeral containers with the envFrom field populated.

    - [SIG VMWare](#sig-vmware-1)
    - [SIG Windows](#sig-windows-1)
  - [Other Notable Changes](#other-notable-changes-11)
    - [Bug Fixes](#bug-fixes)
    - [Not Very Notable (that is, non-user-facing)](#not-very-notable-that-is-non-user-facing)
  - [External Dependencies](#external-dependencies)
- [v1.12.0-rc.2](#v1120-rc2)
  - [Downloads for v1.12.0-rc.2](#downloads-for-v1120-rc2)
    - [Client Binaries](#client-binaries-11)

* `kubectl create rolebinding` and `kubectl create clusterrolebinding` invocations must be updated to  specify multiple subjects as repeated  `--user`, `--group`, or `--serviceaccount` arguments instead of comma-separated arguments to a single `--user`, `--group`, or `--serviceaccount`.  E.g. `--user=x,y` must become `--user x --user y`  ([#43903](https://github.com/kubernetes/kubernetes/pull/43903), [@xilabao](https://github.com/xilabao))


### kubeadm

  // +optional
  optional string path = 2;

  // user is Optional: User is the rados user name, default is admin
  // More info: https://examples.k8s.io/volumes/cephfs/README.md#how-to-use-it
  // +optional
  optional string user = 3;

  // secretFile is Optional: SecretFile is the path to key ring for User, default is /etc/ceph/user.secret
  // More info: https://examples.k8s.io/volumes/cephfs/README.md#how-to-use-it