Control: 5.2.2 Minimize the admission of containers wishing to share the host process ID namespace
Description
Do not generally permit containers to be run with the hostPID flag set to true.
A container running in the host's PID namespace can inspect processes running outside the container. If the container also has access to ptrace capabilities this can be used to escalate privileges outside of the container.
There should be at least one PodSecurityPolicy (PSP) defined which does not permit containers to share the host PID namespace.
If you need to run containers which require hostPID, 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.hostPID 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_2
Snapshot and share results via Turbot Pipes:
powerpipe loginpowerpipe control run kubernetes_compliance.control.cis_kube_v120_v100_5_2_2 --share
SQL
This control uses a named query:
pod_security_policy_hostpid_sharing_disabled