A flaw was found in the Linux kernel. The existing KVM SEV API has a vulnerability that allows a non-root (host) user-level application to crash the host kernel by creating a confidential guest VM instance in AMD CPU that supports Secure Encrypted Virtualization (SEV).
https://www.debian.org/security/2022/dsa-5257
https://lists.debian.org/debian-lts-announce/2022/11/msg00001.html