Information
Do not generally permit containers to be run with the hostIPC flag set to true.
Rationale:
A container running in the host's IPC namespace can use IPC to interact with processes outside the container.
There should be at least one PodSecurityPolicy (PSP) defined which does not permit containers to share the host IPC namespace.
If you have a requirement to containers which require hostIPC, 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.
Solution
Create a PSP as described in the Kubernetes documentation, ensuring that the .spec.hostIPC field is omitted or set to false.
Impact:
Pods defined with spec.hostPID: true will not be permitted unless they are run under a specific PSP.