CVE-2026-13622

Summary

A symlink following vulnerability was found in KubeVirt's virt-handler migration proxy. During live migration, virt-handler dials Unix sockets inside the target virt-launcher pod via /proc/<pid>/root/ paths using net.Dial() without symlink protection. These socket paths reside in qemu-owned directories writable by the virt-launcher user. An attacker with namespace edit and pods/exec permissions can replace a migration proxy socket with a symlink to the host CRI-O socket. Because virt-handler runs as root in the host mount namespace, absolute symlink targets resolve against the host filesystem, and the bidirectional io.Copy proxy relays attacker-controlled bytes to the container runtime, enabling full node compromise.

Affected Software

VendorProductVersion RangeStatus

Weaknesses

  • CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Workarounds

Restrict pods/exec permissions in namespaces that run virtual machines. The pods/exec RBAC permission is required for the attack — removing it from VM operator roles prevents exploitation.

Additionally, enable Kubernetes audit logging and monitor for kubectl exec commands targeting virt-launcher pods, especially during live migration events.

References