Control: 5.2.4 Minimize the admission of containers wishing to share the host network namespace
Description
Do not generally permit containers to be run with the hostNetwork flag set to true.
A container running in the host's network namespace could access the local loopback device, and could access network traffic to and from other pods.
There should be at least one PodSecurityPolicy (PSP) defined which does not permit containers to share the host network namespace.
If you have need to run containers which require hostNetwork, this should be defined in a separate PSP and you should carefully check RBAC controls to ensure that only limited service accounts and users are given permission to access that PSP.
Remediation
Create a PSP as described in the Kubernetes documentation, ensuring that the .spec.hostNetwork field is omitted or set to false.
References
Usage
Run the control in your terminal:
powerpipe control run kubernetes_compliance.control.cis_kube_v120_v100_5_2_4Snapshot and share results via Turbot Pipes:
powerpipe loginpowerpipe control run kubernetes_compliance.control.cis_kube_v120_v100_5_2_4 --shareSQL
This control uses a named query:
pod_security_policy_host_network_access_disabled