cve 2026-31590

CVE-2026-31590 is a Linux kernel vulnerability in KVM's AMD SEV memory-encryption path. The issue involves a userspace-controlled region size that can trigger a kernel warning via KVM_MEMORY_ENCRYPT_REG_REGION. On hardened hosts configured to panic on warnings, this can become a local denial-of-service risk for confidential virtual machines. This is a Linux/KVM host-side issue, not a traditional Windows desktop flaw, but it is relevant for Windows users running virtualized environments on affected hosts. The vulnerability underscores the importance of patching Linux kernel updates in virtualization stacks to maintain security and stability.