Kubevirt: virt-handler-rhel9: kubevirt: virt-handler notify server trusts vmi identity from unauthenticated grpc request body
A flaw was found in KubeVirt's virt-handler domain notify server. The gRPC handlers for HandleDomainEvent and HandleK8SEvent derive the VMI identity (namespace/name) solely from the request body without validating it against the connection's origin. Each virt-launcher pod connects through a per-VMI pipe socket, but no identity tag is propagated from the pipe path to the server handlers. This allows a compromised virt-launcher process to send forged domain lifecycle events for any other VMI scheduled on the same node, causing virt-handler to erroneously update that VMI's state and disrupt its lifecycle management.
Organizations can reduce exposure by: (1) restricting pods/exec permission on virt-launcher pods via admission policies (e.g., Gatekeeper or Kyverno rules denying exec on pods with the kubevirt.io launcher label), (2) using node affinity or dedicated node pools to isolate high-security tenant workloads from untrusted tenants, and (3) monitoring for unexpected VMI state transitions via cluster alerting.
Exploits
Credits
This issue was discovered by Huzaifa Sidhpurwala (Red Hat).