High [CVE-2026-13201] safepath symlink following in virt-handler enables notify socket hijacking and node-level VM disruption

A flaw was found in KubeVirt's safepath package used by virt-handler. The OpenAtNoFollow function uses O_PATH|O_NOFOLLOW to obtain a file descriptor to a path leaf, but downstream operations resolve the path via /proc/self/fd/N using link-following syscalls.

When the leaf is a symlink, the kernel dereferences it, defeating the intended no-follow protection. An attacker with access to a virt-launcher pod can exploit this to redirect virt-handler's IPC socket connections, including the notify socket used for VM domain lifecycle events.

By hijacking this socket, the attacker can inject arbitrary domain events into virt-handler, causing it to take incorrect lifecycle actions, corrupt VM state in the Kubernetes API, or crash — resulting in sustained denial of VM management services for all virtual machines on the affected node.

Additionally, the same symlink following flaw allows virt-handler to apply file ownership or permission changes to unintended host paths. The primary impact is through notify socket hijacking: virt-handler uses safepath to resolve the path to the notify socket inside each virt-launcher pod.

A namespace-level tenant with pod access can replace this socket path with a symlink to an attacker-controlled socket, enabling injection of arbitrary VM domain lifecycle events.