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.

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.

kubevirt1.9-container-disk-1.9.0-3.1 on GA media

kubevirt: virt-handler-rhel9: kubevirt: virt-handler migration proxy follows symlinks allowing container escape to host