CVE-2026-122192 is a vulnerability in Firecracker versions 0.23.0 through 1.16.1 that allows a root user in a guest VM to read or modify memory of the Firecracker process on the host. This occurs when restoring VMs from snapshots using the File memory backend with a balloon or virtio-mem device, due to a failed memory remapping operation that leaves stale host virtual address references. The issue is fixed in Firecracker versions 1.16.2 and 1.17.0 and later. AWS Lambda and other AWS services are not affected. No customer action is required for AWS-managed services.