Rancher's restricted PodSecurityPolicy does not prevent containers from running as a privileged user
Date: 2026-03
Affected: go/github.com/rancher/rancher
Attack vector: auth-bypass
Category: vulnerability-disclosure
Severity: High
CWE: CWE-862

### Impact The `restricted` pod security policy (PSP), provided in Rancher versions from 2.0 up to and including 2.6.3, has a deviation from the [upstream](https://github.com/kubernetes/website/blob/6d22e08903d7dd44b049c4689fa882ae07f67de9/content/en/examples/policy/restricted-psp.yaml) `restricted` policy provided in Kubernetes, in which Rancher's PSP has `runAsUser` set to `runAsAny`, while upstream has `runAsUser` set to `MustRunAsNonRoot`. This allows containers to run as any user, including a privileged user (`root`), even when Rancher's `restricted` policy is enforced on a project or at cluster level. A new `restricted-noroot` PSP was created to prevent pods from running as `root` when this policy is enforced. This new policy was introduced, instead of patching the current provided `restricted` policy, in order to avoid breaking users' workloads that are using the `restricted` PSP and that might be running as a privileged user. **Note**: Running containers as `root` increases the risk of a compromised container being used by a malicious actor as an attack platform to further exploit the user's environment. It is a security best practice to avoid running containers as a privileged user and to limit its usage to workloads where it is strictly necessary. ### Patches Patched versions include release 2.6.4 and later versions. The existing `restricted` PSP in Rancher 2.6.4 was not modified and still allows containers to run as a privileged user, as explained above. This f


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