kyverno/samples/DisallowHostNetworkPort.md

Disallow hostNetwork and hostPort

Using hostPort and hostNetwork allows pods to share the host networking stack allowing potential snooping of network traffic across application pods.

Policy YAML

disallow_host_network_hostport.yaml

apiVersion: kyverno.io/v1alpha1
kind: ClusterPolicy
metadata:
  name: validate-host-network-hostport
spec:
  rules:
  - name: validate-host-network-hostport
    match:
      resources:
        kinds:
        - Pod
    validate:
      message: "Defining hostNetwork and hostPort are not allowed."
      pattern:
        spec:
          (hostNetwork): false
          containers:
          - name: "*"
            ports:
            - hostPort: null