Executive brief
Rancher Local Path Provisioner, a tool for managing local storage in Kubernetes, is vulnerable to a template injection flaw. An attacker with administrative-level access to specific configuration settings can manipulate how system pods are created. This could allow them to bypass security boundaries, access sensitive files on the underlying server, and potentially take control of the entire computing node.
Technical details
A template injection vulnerability exists in rancher/local-path-provisioner due to insufficient validation of the helperPod.yaml template stored in the local-path-config ConfigMap. An attacker with permissions to edit this ConfigMap can inject security-sensitive fields such as securityContext.privileged: true, hostPath volumes, or dangerous Linux capabilities. When the provisioner subsequently creates a HelperPod for PVC provisioning or cleanup, it uses the malicious template, resulting in a privileged pod with host root access. This allows for node-level compromise, including access to other tenants' data and ServiceAccount tokens. The issue is fixed in version 0.0.36 by implementing strict validation of the template fields.
Affected products
- Rancher local-path-provisioner < 0.0.36
Timeline
- 2026-05-08: disclosed: Initial disclosure by researchers
- 2026-05-11: advisory: GitHub Advisory published
- 2026-05-28: other: NVD publication date