Cis Ocp V160 1.1.5

CIS Red Hat OpenShift Container Platform Benchmark v1.6.0 - Control 1.1.5

Profile Applicability

• Level: 1

Description

Ensure that the scheduler pod specification file has permissions of 600 or more restrictive.

Rationale

The scheduler pod specification file controls various parameters that set the behavior of the Scheduler service in the master node. You should restrict its file permissions to maintain the integrity of the file. The file should be writable by only the administrators on the system.

Impact

None.

Audit Procedure

In OpenShift 4 the kube-scheduler is deployed as a static pod and its pod specification file is created on control plane nodes at /etc/kubernetes/manifests/kube-scheduler-pod.yaml. It is mounted via hostpath to the kube-controller-manager pods via /etc/kubernetes/static-pod-resources/kube-scheduler-pod.yaml with permissions 644. To verify, run the following command.

for i in $(oc get pods -n openshift-kube-scheduler -l app=openshift-kube-scheduler -o name)
 do
  oc exec -n openshift-kube-scheduler $i -- \
  stat -c %a /etc/kubernetes/static-pod-resources/kube-scheduler-pod.yaml
 done

Verify that the permissions are 600 or more restrictive.

Remediation

There is no remediation for updating the permissions of kube-scheduler-pod.yaml. The file is owned by an OpenShift operator and any changes to the file will result in a degraded cluster state. Please do not attempt to remediate the permissions of this file.

Default Value

By default, in OpenShift 4.14, the kube-scheduler-pod.yaml has permissions of 600.

In older versions of OpenShift, the kube-scheduler-pod.yaml has permissions of 644, and is not remediable. Please upgrade to OpenShift 4.14 when possible.

References

1. https://docs.openshift.com/container-platform/latest/architecture/control-plane.html#defining-masters_control-plane
2. https://github.com/openshift/library-go/commit/19a42d2bae8ba68761cfad72bf764e10d275ad6e
3. https://kubernetes.io/docs/reference/command-line-tools-reference/kube-scheduler/

CIS Controls

MITRE ATT&CK Mappings

Profile

Level 1 (Manual)