CVE-2026-23401
Gravedad:
Pendiente de análisis
Tipo:
No Disponible / Otro tipo
Fecha de publicación:
01/04/2026
Última modificación:
02/04/2026
Descripción
*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br />
<br />
KVM: x86/mmu: Drop/zap existing present SPTE even when creating an MMIO SPTE<br />
<br />
When installing an emulated MMIO SPTE, do so *after* dropping/zapping the<br />
existing SPTE (if it&#39;s shadow-present). While commit a54aa15c6bda3 was<br />
right about it being impossible to convert a shadow-present SPTE to an<br />
MMIO SPTE due to a _guest_ write, it failed to account for writes to guest<br />
memory that are outside the scope of KVM.<br />
<br />
E.g. if host userspace modifies a shadowed gPTE to switch from a memslot<br />
to emulted MMIO and then the guest hits a relevant page fault, KVM will<br />
install the MMIO SPTE without first zapping the shadow-present SPTE.<br />
<br />
------------[ cut here ]------------<br />
is_shadow_present_pte(*sptep)<br />
WARNING: arch/x86/kvm/mmu/mmu.c:484 at mark_mmio_spte+0xb2/0xc0 [kvm], CPU#0: vmx_ept_stale_r/4292<br />
Modules linked in: kvm_intel kvm irqbypass<br />
CPU: 0 UID: 1000 PID: 4292 Comm: vmx_ept_stale_r Not tainted 7.0.0-rc2-eafebd2d2ab0-sink-vm #319 PREEMPT<br />
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015<br />
RIP: 0010:mark_mmio_spte+0xb2/0xc0 [kvm]<br />
Call Trace:<br />
<br />
mmu_set_spte+0x237/0x440 [kvm]<br />
ept_page_fault+0x535/0x7f0 [kvm]<br />
kvm_mmu_do_page_fault+0xee/0x1f0 [kvm]<br />
kvm_mmu_page_fault+0x8d/0x620 [kvm]<br />
vmx_handle_exit+0x18c/0x5a0 [kvm_intel]<br />
kvm_arch_vcpu_ioctl_run+0xc55/0x1c20 [kvm]<br />
kvm_vcpu_ioctl+0x2d5/0x980 [kvm]<br />
__x64_sys_ioctl+0x8a/0xd0<br />
do_syscall_64+0xb5/0x730<br />
entry_SYSCALL_64_after_hwframe+0x4b/0x53<br />
RIP: 0033:0x47fa3f<br />
<br />
---[ end trace 0000000000000000 ]---
Impacto
Referencias a soluciones, herramientas e información
- https://git.kernel.org/stable/c/459158151a158a6703b49f3c9de0e536d8bd553f
- https://git.kernel.org/stable/c/695320de6eadb75aaed8be1787c4ce4c189e4c7b
- https://git.kernel.org/stable/c/aad885e774966e97b675dfe928da164214a71605
- https://git.kernel.org/stable/c/bce7fe59d43531623f3e43779127bfb33804925d
- https://git.kernel.org/stable/c/fd28c5618699180cd69619801e9ae6a5266c0a22



