KubernetesOverview
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 admission control policy 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 policy and you should carefully check to ensure that only limited service accounts and users are given permission to use that policy.
Remediation guidance
Add policies to each namespace in the cluster which has user workloads to restrict the admission of hostPID containers.
Multiple Remediation Paths
SERVICE-WIDE (RECOMMENDED when many resources are affected): Apply organization/tenant-level guardrails and baseline policies for the entire platform.
ASSET-LEVEL: Fix only the affected resources identified by this control.
PREVENTIVE: Add preventive policy checks to CI/CD and periodic posture scans.
References for Service-Wide Patterns
- Platform policy/governance and preventive control patterns should be applied tenant-wide where supported.
Query logic
These are the stored checks tied to this control.
Check there are restrictions on the creation of hostPID pods
Connectors
Covered asset types
Expected check: eq []
{
pods(where: { hostPID: true NOT: { namespace: "kube-system" } }) {
...AssetFragment
}
}
