CVE-2026-9804: Kubevirt: kubevirt: vmexport directory symlink escape enables exporter pod file read

Synopsis

A path traversal vulnerability via symlink escape affects KubeVirt's virt-exportserver component in Red Hat OpenShift Virtualization 4. An authenticated attacker with namespace-level access can place a symbolic link inside an exported PVC that points outside the designated mount root, tricking the exporter pod into following it. Successful exploitation allows the attacker to read arbitrary files from the exporter pod's filesystem, disclosing sensitive data. HarborGuard tracks this advisory and will make a patched-image rebuild available as soon as an upstream fix is published.

HarborGuard Coverage

Exploit Conditions

• Network reachabilityRequired

  The virt-exportserver endpoint is exposed over the network, so the attacker must be able to reach the service across the network to interact with the VMExport directory endpoint.

• AuthenticationRequired

  The attacker must hold a valid low-privilege account with namespace-level access; no admin credentials are needed, but unauthenticated access is not sufficient.

• Victim interactionNot required

  No user interaction or social-engineering step is needed; the attacker manipulates the exported PVC directly without involving another party.

• Attack complexityDetail

  Attack complexity is low, meaning the exploit is reliable and requires no special race conditions, memory layout dependencies, or other environmental factors beyond having the necessary namespace access.

Blast Radius

• The attacker reads arbitrary files from the exporter pod's filesystem, including mounted secrets, service-account tokens, and configuration files visible to that pod.
• Kubernetes service-account credentials or TLS private keys stored in the pod's filesystem can be extracted and reused to escalate access within the cluster.
• Application configuration files containing database connection strings, API keys, or other credentials become readable without any modification to the running workload.