Potential impacts:

   ([#122729](https://github.com/kubernetes/kubernetes/pull/122729), [@jparrill](https://github.com/jparrill))

### SIG Big Data

During the 1.13 release cycle, SIG Big Data has been focused on community engagements relating to 3rd-party project integrations with Kubernetes. There have been no impacts on the 1.13 release.

### SIG CLI

by this vulnerability if you run a Validating Admission Webhook for Nodes
that denies admission based at least partially on the old state of the
Node object.

**Note**: This only impacts validating admission plugins that rely on old
values in certain fields, and does not impact calls from kubelets that go
through the built-in NodeRestriction admission plugin.

**Affected Versions**:
  - kube-apiserver v1.20.0 - v1.20.5

serving watch requests without a resourceVersion from the watch cache by default, as in <1.27 (disabling the change in #115096 by default). This mitigates the impact of an etcd watch bug (https://github.com/etcd-io/etcd/pull/17555). If the 1.27 change in #115096 to serve these requests from underlying storage is still desired despite the impact on watch stability, it can be re-enabled with a `WatchFromStorageWithoutResourceVersion` feature gate. ([#124007](https://github.com/kubernetes/kubernetes/pull/124007),...

service account's secrets field. Kubernetes clusters are only affected if the ServiceAccount admission plugin and the `kubernetes.io/enforce-mountable-secrets` annotation are used together with ephemeral containers.

**Note**: This only impacts the cluster if the ServiceAccount admission plugin is used (most cluster should have this on by default as recommended in https://kubernetes.io/docs/reference/access-authn-authz/admission-controllers/#serviceaccount), the `kubernetes.io/enforce-mountable-secrets`...

that denies admission based at least partially on the old state of the
Node object.

**Note**: This only impacts validating admission plugins that rely on old
values in certain fields, and does not impact calls from kubelet that go
through the built-in NodeRestriction admission plugin.

**Affected Versions**:
  - kube-apiserver v1.20.0 - v1.20.5

service account's secrets field. Kubernetes clusters are only affected if the ServiceAccount admission plugin and the `kubernetes.io/enforce-mountable-secrets` annotation are used together with ephemeral containers.

**Note**: This only impacts the cluster if the ServiceAccount admission plugin is used (most cluster should have this on by default as recommended in https://kubernetes.io/docs/reference/access-authn-authz/admission-controllers/#serviceaccount), the `kubernetes.io/enforce-mountable-secrets`...

service account's secrets field. Kubernetes clusters are only affected if the ServiceAccount admission plugin and the `kubernetes.io/enforce-mountable-secrets` annotation are used together with ephemeral containers.

**Note**: This only impacts the cluster if the ServiceAccount admission plugin is used (most cluster should have this on by default as recommended in https://kubernetes.io/docs/reference/access-authn-authz/admission-controllers/#serviceaccount), the `kubernetes.io/enforce-mountable-secrets`...

* iSCSI sessions managed by kubernetes will now explicitly set startup.mode to 'manual' to  prevent automatic login after node failure recovery. This is the default open-iscsi mode, so this change will only impact users who have changed their startup.mode to be 'automatic' in /etc/iscsi/iscsid.conf. ([#57475](https://github.com/kubernetes/kubernetes/pull/57475), [@stmcginnis](https://github.com/stmcginnis))