CVE-2026-44543: Local Path Provisioner: HelperPod Template Injection

Synopsis

This is a template-injection vulnerability in Rancher Local Path Provisioner, a Kubernetes component that manages local-storage PersistentVolumeClaims. An attacker with admin-level access to the local-path-config ConfigMap in the local-path-storage namespace can inject arbitrary pod security fields into the helperPod.yaml template, causing the provisioner to spawn a privileged HelperPod with the host root filesystem mounted during PVC operations. Successful exploitation gives the attacker read and write access to sensitive host files, ServiceAccount tokens from co-located pods, and other tenants' volume data. No fix version has been published yet; HarborGuard is tracking the upstream advisory and will surface a patched-image rebuild the moment a fix is released.

HarborGuard Coverage

Exploit Conditions

• Network reachabilityRequired

  The provisioner's Kubernetes API endpoint must be reachable over the network; an attacker edits the ConfigMap via standard Kubernetes API calls from any networked client.

• AuthenticationRequired

  The attacker must hold a Kubernetes account or token with write permission on the local-path-config ConfigMap in the local-path-storage namespace, making an admin or equivalently privileged credential a prerequisite.

• Victim interactionNot required

  No human interaction is needed; exploitation completes when the provisioner next creates a HelperPod in response to a PVC provisioning or cleanup operation.

• Attack complexityDetail

  The exploit is reliable and condition-free once the ConfigMap write permission is held; no race conditions or special environmental factors are required.

Blast Radius

• Reads sensitive host files, including /etc/shadow, SSH keys, and kubelet credentials, by mounting the node's root filesystem into the injected privileged pod.
• Reads ServiceAccount tokens from other pods co-located on the same node, enabling lateral movement to any Kubernetes workload whose identity is bound to a powerful RBAC role.
• Reads other tenants' local-path volume data stored on the same node, breaking storage isolation between namespaces.
• Writes to or modifies files on the host node filesystem, including binary paths and systemd units, enabling persistent compromise of the underlying node.