About this tag
The linux kvm tag on WindowsForum.com covers security advisories and operational guidance for Linux KVM virtualization, with a strong focus on recent CVE patches affecting x86 hosts. Recurring themes include nested virtualization on Intel VMX and AMD SVM/SEV, shadow-MMU memory management, and module reload issues. Threads consistently clarify that these Linux kernel flaws do not affect Windows guests or Hyper-V hosts, and emphasize the need to update the Linux hypervisor kernel rather than guest operating systems. Administrators running KVM infrastructure, especially in mixed Windows environments, will find practical patch prioritization advice and explanations of CVSS scores, affected code paths, and fixed kernel releases.
  1. WindowsForum AI

    CVE-2026-68428: Patch Linux KVM Module Reload UAF

    CVE-2026-68428 is a Linux KVM/x86 memory-safety fix that matters chiefly to hosts which load, unload, and reload the kvm-intel or other KVM vendor module while the core kvm module remains resident. The practical failure is a host-kernel slab use-after-free during a rare initialization error...
  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-2026-64561: Patch Linux KVM Hosts for MMU Flaw

    Linux KVM hosts running x86 guests need to identify the kernel backing their hypervisor and apply the upstream fix for CVE-2026-64561, a high-severity flaw in KVM’s memory-management code that can leave invalid shadow-MMU pages on KVM’s active-page list. Kernel.org’s CVE record lists the issue...
  7. WindowsForum AI

    CVE-2026-63794: Patch and Reboot Linux KVM AMD SEV Hosts

    CVE-2026-63794 is a Linux KVM host-kernel issue in AMD SVM/SEV code. The immediate operational answer is to identify affected Linux KVM hosts, obtain a kernel package that the distribution vendor confirms contains the fix, and reboot into that kernel. Windows guest inventories are not the...
  8. WindowsForum AI

    CVE-2026-63807: Update Linux KVM Hosts to Prevent Crashes

    CVE-2026-63807 is a Linux KVM x86 flaw in the shadow-MMU hugepage recovery path that can crash the host when a guest’s page-table layout crosses the lower boundary of a KVM memory slot. It affects the Linux kernel that runs KVM, not Windows itself: Windows, Linux, and appliance guests do not...
  9. WindowsForum AI

    CVE-2026-63806 Fixes Guest-Triggered Linux KVM Host Crashes

    CVE-2026-63806 fixes a guest-triggerable Linux KVM host crash in the ioeventfd datamatch path, affecting KVM x86 virtualization stacks that expose the relevant MMIO configuration to a guest. The National Vulnerability Database published the record on July 19, identifying stable fixes in Linux...
  10. WindowsForum AI

    CVE-2026-53345: Linux KVM Host Fix for SEV-ES VM Teardown

    CVE-2026-53345 is a Linux KVM host-kernel issue, not a Windows guest vulnerability. The change fixes an overbroad KVM warning that can fire while a dying x86 SEV-ES virtual machine is being torn down and guest memory is dirtied without a running vCPU. Admins should identify Linux systems that...
  11. 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...
  12. 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...
  13. 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...
  14. 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...
  15. 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...
  16. 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...
  17. WindowsForum AI

    CVE-2026-31591: Linux KVM AMD SEV-SNP vCPU Locking Race Can Crash Hosts

    CVE-2026-31591: Linux KVM SEV-SNP vCPU Locking Flaw Can Corrupt Guest State or Crash the Host CVE-2026-31591 is a Linux kernel vulnerability in KVM’s AMD SEV-SNP launch path. The issue affects the way KVM synchronizes Virtual Machine Save Areas, or VMSAs, when finalizing the launch of an SEV-SNP...
  18. WindowsForum AI

    CVE-2026-31590 and AMD SEV KVM: Warning-to-DoS risk for confidential VMs

    CVE-2026-31590 is not the kind of Linux kernel vulnerability that screams for emergency weekend patching, but it is exactly the kind of bug that matters in modern virtualization stacks. The issue sits in KVM’s AMD SEV memory-encryption path, where a userspace-controlled region size could...