Runs With the Root Group (GID 0)

apiVersion: admissionregistration.k8s.io/v1
kind: ValidatingAdmissionPolicy
metadata:
  name: initcontainer-run-as-group
  annotations:
    kubeapt.io/uuid: "14da0518-3885-4dcc-b859-a23056ea44d6"
    security.kubeapt.io/displayName: "Runs With the Root Group (GID 0)"
    security.kubeapt.io/description: "An init container running with GID 0 places its processes in the root group, which owns or can write many files in images and mounted host volumes, widening what a compromised process reaches."
    security.kubeapt.io/resource: "InitContainers"
    security.kubeapt.io/severity: "Moderate"
    security.kubeapt.io/remediation: "Set runAsGroup to a non-zero GID such as 1000, or leave it unset. Field: spec.initContainers[*].securityContext.runAsGroup."
    security.kubeapt.io/product: "Kubernetes"
spec:
  failurePolicy: Fail
  matchConstraints:
    resourceRules:
    - apiGroups:
      - ''
      apiVersions:
      - v1
      operations:
      - CREATE
      - UPDATE
      resources:
      - pods
  validations:
  - expression: |
      !has(object.spec.initContainers) || object.spec.initContainers.all(ic,
        !has(ic.securityContext) ||
        !has(ic.securityContext.runAsGroup) ||
        ic.securityContext.runAsGroup > 0
      )
    message: |
      spec.initContainers[*].securityContext.runAsGroup must be undefined or a non-zero value (> 0).