Ensure the admission control plugin AlwaysPullImages is set

Error: The admission control plugin AlwaysPullImages is not set

Bridgecrew Policy ID: BC_K8S_57
Checkov Check ID: CKV_K8S_80
Severity: MEDIUM

The admission control plugin AlwaysPullImages is not set

Description

Always pull images.
Setting admission control policy to AlwaysPullImages forces every new pod to pull the required images every time. In a multi-tenant cluster users can be assured that their private images can only be used by those who have the credentials to pull them. Without this admission control policy, once an image has been pulled to a node, any pod from any user can use it simply by knowing the image’s name, without any authorization check against the image ownership. When this plug-in is enabled, images are always pulled prior to starting containers, which means valid credentials are required.

Fix - Buildtime

Kubernetes

  • Kind: Pod
apiVersion: v1
kind: Pod
metadata:
  creationTimestamp: null
  labels:
    component: kube-apiserver
    tier: control-plane
  name: kube-apiserver
  namespace: kube-system
spec:
  containers:
  - command:
+   - kube-apiserver
+   - --enable-admission-plugins=AlwaysPullImages
    image: gcr.io/google_containers/kube-apiserver-amd64:v1.6.0
    ...

Did this page help you?