Kubetier
← Permission Reference
T1

create persistentvolumeclaims

Grants host filesystem access by binding a PVC to an existing hostPath PV, no create permission on persistentvolumes required.

API Group
(core)
Scope
namespaced
Audit Level
Request

Escalation Paths

  1. Create a hostPath PersistentVolume mounting node / (or use an existing one via a PVC)

  2. Claim the volume from an otherwise restricted-compliant pod.

    PSA does not inspect the PV behind a PVC, so even the restricted profile does not block it

  3. Read or write arbitrary node filesystem paths.

    This is T0 on control plane nodes

  4. Or set the PV's claimRef to a victim's PVC name and namespace, including one not yet created, so the victim's future workload silently binds to attacker-controlled storage

Additional rights needed:

Note:

The base hostPath PV path is not version-patched, and Pod Security Admission does not block it at any profile.

PSA checks the pod's own volume types, never the PV behind a PVC.

runAsNonRoot only limits which host files are readable, not the mount.

CVE-2021-25741 is a separate, patched issue.

K8s docs ↗

Included in Built-in Roles

K8s docs ↗