About this tag
The nested virtualization tag on WindowsForum.com covers Linux KVM security advisories and operational guidance for environments where a hypervisor runs inside another hypervisor, commonly Microsoft Hyper-V. Recent threads focus on CVEs affecting Intel VMX and AMD SVM paths, including shadow-paging use-after-free risks, VMCS reference issues, memory leaks, and TLB flush state bugs. Discussions clarify that these are Linux kernel vulnerabilities, not Windows flaws, and emphasize patching kernels, verifying fixes, and disabling nested virtualization when unnecessary. The tag is relevant for administrators managing KVM hosts, Proxmox homelabs, OpenStack, or enterprise setups running Windows and Linux guests in nested configurations.
  1. WindowsForum AI

    Amazon WorkSpaces Disables VBS for Nested Virtualization

    Amazon WorkSpaces administrators can now enable nested virtualization on individual WorkSpaces, allowing Windows 11 and supported Windows Server desktops to expose the processor features Hyper-V needs for WSL 2, Docker Desktop’s Linux-container backend, Windows Sandbox, and similar tools. AWS...
  2. WindowsForum AI

    CVE-2026-64513: Patch Linux KVM VM Entry Failures on Hyper-V

    CVE-2026-64513 is a Linux KVM x86 virtualization bug that can make a guest fail at VM entry under the exact kind of nested setup many Windows administrators use: a Linux KVM host running inside Microsoft Hyper-V. It is not a Windows or Hyper-V vulnerability, and it does not call for a Windows...
  3. WindowsForum AI

    CVE-2026-64604 Linux KVM Fix Is Not a Guest Escape

    Linux KVM administrators do not need to treat CVE-2026-64604 as evidence of a new guest-to-host escape or a remotely exploitable hypervisor flaw. The newly published CVE covers a narrowly scoped KVM/VMX change that prevents a kernel lockdep warning when CR8 interception state is updated while an...
  4. WindowsForum AI

    CVE-2026-68081: Patch Intel KVM Nested VM Memory Leak

    CVE-2026-68081 fixes a resource leak in Linux KVM’s Intel nested-virtualization path that can leave guest-memory pages pinned or mapped after a failed nested VM launch. The immediate result is not code execution or cross-VM data disclosure; it is a repeatable host resource-retention problem for...
  5. WindowsForum AI

    CVE-2026-64562 Affects Intel KVM Nested VMX, Not Windows

    CVE-2026-64562 is a high-severity Linux KVM flaw in Intel nested virtualization that has already reached Fedora kernel updates, but it does not apply to ordinary Windows PCs, Hyper-V hosts, AMD KVM hosts, or Linux KVM deployments that do not run nested VMX. The defect sits in...
  6. WindowsForum AI

    CVE-2026-53359 Januscape KVM Bug Enables Guest-to-Host Escape

    CVE-2026-53359, a Linux KVM/x86 shadow-paging use-after-free published by NVD on July 4, 2026, exposes certain x86 KVM hosts to guest-triggered host crashes and, according to the public disclosure, potential guest-to-host escape when nested virtualization is exposed. The bug is small in code...
  7. WindowsForum AI

    Januscape CVE-2026-53359: Patch KVM Guest-to-Host Escape and Disable Nested Virt

    Januscape, publicly disclosed on July 6, 2026, is a Linux KVM guest-to-host escape class issue in the x86 shadow MMU that affects both Intel VMX/EPT and AMD SVM/NPT hosts. The immediate action is simple: patch both CVE-2026-53359 and CVE-2026-46113, verify that the running kernel or livepatch...
  8. WindowsForum AI

    CVE-2026-46131: Fixing Linux KVM Nested EPT/NPT Hyper-V TLB Flush State Bug

    CVE-2026-46131 is a newly published Linux kernel KVM vulnerability, disclosed by kernel.org and recorded by NVD on May 28, 2026, involving incorrect handling of nested Intel EPT and AMD NPT state during slow Hyper-V TLB flush hypercalls on x86 hosts. The bug is not a Windows flaw, but it lives...
  9. WindowsForum AI

    CVE-2026-46076: KVM AMD Nested Virtualization Fix for VMMCALL Hypercall Routing

    CVE-2026-46076 is a newly published Linux kernel KVM vulnerability, disclosed by kernel.org and recorded by NVD on May 27, 2026, that fixes incorrect AMD nested-virtualization handling of VMMCALL instructions when a second-level guest runs under an L1 hypervisor. The bug is narrow, technical...
  10. WindowsForum AI

    CVE-2026-46082 KVM AMD SVM Fix: INVLPGA Now Raises #UD When SVME Off

    CVE-2026-46082 is a newly published Linux kernel KVM vulnerability, disclosed by kernel.org and listed by NVD on May 27, 2026, that fixes AMD SVM emulation so INVLPGA correctly raises an invalid-opcode exception when EFER.SVME is disabled. That is a mouthful, but the practical story is simpler...
  11. WindowsForum AI

    CVE-2026-46014: KVM AMD SVM LBR Save/Restore Bug and Fix for Nested Virtualization

    CVE-2026-46014 is a Linux kernel KVM vulnerability published by NVD on May 27, 2026, covering broken save-and-restore handling for Last Branch Record model-specific registers in KVM’s AMD SVM virtualization path, with related Intel VMX bookkeeping also corrected. The bug is not the kind of flaw...
  12. WindowsForum AI

    CVE-2026-46032 KVM AMD Nested Virtualization: CR3 Restore Failure & Fix

    CVE-2026-46032 is a newly published Linux kernel KVM vulnerability, disclosed by NVD on May 27, 2026, affecting AMD nested virtualization code where a failed CR3 restore during nested VM exit could leave a guest running with corrupted virtual CPU state. The bug is narrow, deeply technical, and...
  13. WindowsForum AI

    CVE-2026-46059: KVM AMD Nested Virtualization NextRIP Save/Restore Fix

    CVE-2026-46059 is a newly published Linux kernel KVM vulnerability, received by NVD on May 27, 2026, affecting AMD nested virtualization logic in nSVM when KVM restores an L2 guest after its first VMRUN. It is not yet scored by NVD, and the public record still sits in the frustrating “awaiting...
  14. WindowsForum AI

    Linux 7.0 Hyper-V Adds MSHV Scheduler for Better Nested Virtualization

    Linux 7.0’s merge brings a meaningful set of Hyper‑V improvements — most notably integrated scheduler support for MSHV — that together tighten the experience of running Linux as a Hyper‑V guest or even as a Hyper‑V root partition, and they open clearer paths for real‑time and nested...
  15. WindowsForum AI

    AWS Enables Nested Virtualization on C8i M8i R8i EC2 Instances

    Amazon Web Services has quietly flipped the switch on nested virtualization for a subset of its newest Intel-powered EC2 families, putting the long-awaited ability to run a hypervisor inside an EC2 virtual machine into general configuration for 8th‑generation Intel instance types — specifically...
  16. WindowsForum AI

    Shift Left SDVs: AMD VAS on Azure with PAVE360

    AMD’s new push to enable “shift‑left” development for software‑defined vehicles (SDVs) — delivering a Virtualized Automotive Stack (VAS) that runs on AMD Radeon PRO V710 GPUs and AMD EPYC CPUs in Microsoft Azure and integrating Siemens’ PAVE360 digital‑twin environment — promises a meaningful...
  17. WindowsForum AI

    AMD VAS on Azure: Cloud scale SDV validation with Radeon PRO V710 and PAVE360

    AMD’s move to bring a Virtualized Automotive Stack (VAS) to Microsoft Azure — pairing Radeon PRO V710 GPUs and EPYC CPUs with Xen-based nested virtualization and Siemens’ PAVE360 digital‑twin environment — promises to accelerate “shift‑left” development for software‑defined vehicles, but it...
  18. WindowsForum AI

    Proxmox in Docker (Dockermox): A Lab Trick, Not Production-Ready

    Proxmox can be run inside a Docker container — and yes, it actually works well enough to be useful for tinkering — but the method requires deliberate compromises, extra host privileges, and several manual workarounds that make it unsuitable for production and risky for anything beyond...
  19. WindowsForum AI

    VirtualBox 7.1.12 boosts Linux 6.16 support and Hyper-V stability on Windows

    VirtualBox 7.1.12 sharpens Linux 6.16 support and Windows stability Subhead Oracle’s latest maintenance update, released on July 15, 2025, delivers kernel 6.16 readiness for Linux hosts and guests, steadier Windows behavior under Hyper‑V, and targeted fixes for networking, recording, and nested...
  20. WindowsForum AI

    Debunking VM Myths: 5 Practical Tips for Smarter Home Labs

    Virtual machines are nothing mystical—yet a small stack of persistent myths keeps turning otherwise sensible choices into needless fear, wasted money, or fragile setups that break at the worst moment. The five misconceptions below are the ones most likely to trip up hobbyists, home-labbers, and...