apiVersion: kyverno.io/v1
kind: ClusterPolicy
metadata:
  name: require-drop-all-capabilities
  annotations:
    policies.kyverno.io/title: Require capabilities.drop ALL
    policies.kyverno.io/category: Pod Security
    policies.kyverno.io/severity: medium
    policies.kyverno.io/description: >-
      Require every container to drop ALL capabilities (add back only what is
      needed).
spec:
  validationFailureAction: Enforce
  background: true
  rules:
    - name: require-capabilities-drop-all
      match:
        any:
          - resources:
              kinds:
                - Pod
      exclude:
        any:
          - resources:
              namespaces:
                - kube-system
                - kube-public
                - kube-node-lease
                - flux-system
                - flux-canary
                - kyverno
                - cert-manager
                - cilium-secrets
                - olm
                - operators
                - longhorn
                - openebs
                - intel-system
                - nfd
      validate:
        message: >-
          Containers must set securityContext.capabilities.drop to include ALL.
        pattern:
          spec:
            =(initContainers):
              - securityContext:
                  capabilities:
                    drop:
                      - ALL
            =(ephemeralContainers):
              - securityContext:
                  capabilities:
                    drop:
                      - ALL
            containers:
              - securityContext:
                  capabilities:
                    drop:
                      - ALL