Affected deployments use Firecracker versions 0.23.0 through 1.16.1, restore microVMs from snapshots with the File memory backend, and have either a balloon or virtio-mem device configured. Deployments that do not meet those configuration conditions are not identified as affected by the provided information.
The attack starts from malicious guest userspace inside a microVM. Successful exploitation can allow the guest to read or overwrite Firecracker VMM process memory and achieve controlled code execution on the host.
Upgrade Firecracker to version 1.16.2 or to version 1.17.0 or later. The vulnerable version range ends at 1.16.1.
Check whether Firecracker is in the 0.23.0–1.16.1 range and whether microVM snapshots are restored using the File memory backend with a balloon or virtio-mem device. All of these conditions are required by the affected configuration described.