NVIDIA BlueField - VIRTIO-Net emulation: MULTI-TENANT ISOLATION: a VM user sends a crafted message to the BlueField

Impact

MULTI-TENANT ISOLATION: a VM user sends a crafted message to the BlueField VIRTIO-Net device and gets a write-what-where primitive, reaching code execution in the VIRTIO-Net context on the DPU. The DPU is the component you offloaded tenant network isolation onto - a tenant VM reaching code execution inside it inverts the trust model of the whole design. Scored 9.0 with a changed scope.

Who can reach it

A user inside a tenant VM talking to the emulated virtio-net device its own hypervisor exposed. No host or DPU credentials needed. This is the guest-to-DPU boundary.

What to do

Update the BlueField VIRTIO-Net firmware/software per bulletin 5815 across GA, LTS23, LTS24 and LTS25 branches as applicable. Cost: a DPU firmware update takes the DPU's dataplane down, which means the host loses network - treat it as a full node drain, not a live update. Sequence carefully: a half-updated DPU fleet has inconsistent offload behaviour.

References