Sets a Custom SELinux User

apiVersion: admissionregistration.k8s.io/v1
kind: ValidatingAdmissionPolicy
metadata:
  name: ephemeralcontainer-selinux-user
  annotations:
    kubeapt.io/uuid: "4598e7df-4c5e-4ee2-a0b5-9ce4179a89fc"
    security.kubeapt.io/displayName: "Sets a Custom SELinux User"
    security.kubeapt.io/description: "A custom SELinux user label replaces the confined context the runtime assigns to the ephemeral container, granting a policy domain with transitions and file access the sandbox was never meant to allow."
    security.kubeapt.io/resource: "EphemeralContainers"
    security.kubeapt.io/severity: "Moderate"
    security.kubeapt.io/remediation: "Remove the seLinuxOptions.user setting from every ephemeral container or leave it as an empty string so the runtime assigns its default SELinux user. Field: spec.ephemeralContainers[*].securityContext.seLinuxOptions.user."
    security.kubeapt.io/product: "Kubernetes"
spec:
  failurePolicy: Fail
  matchConstraints:
    resourceRules:
    - apiGroups:
      - ''
      apiVersions:
      - v1
      operations:
      - CREATE
      - UPDATE
      resources:
      - pods/ephemeralcontainers
  validations:
  - expression: |
      !has(object.spec.ephemeralContainers) || object.spec.ephemeralContainers.all(ec,
        !has(ec.securityContext) ||
        !has(ec.securityContext.seLinuxOptions) ||
        !has(ec.securityContext.seLinuxOptions.user) ||
        ec.securityContext.seLinuxOptions.user == ""
      )
    message: |
      spec.ephemeralContainers[*].securityContext.seLinuxOptions.user must be undefined or an empty string ("").