CVE-2026-23401KVM: x86/mmu: Drop/zap existing present SPTE even when creating an MMIO SPTE
Updated under an hour ago ()
Does this affect you?
It affects Linux and 7 other products. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
Do this next
Free account, 1 product
In the Linux kernel, the following vulnerability has been resolved: KVM: x86/mmu: Drop/zap existing present SPTE even when creating an MMIO SPTE When installing an emulated MMIO SPTE, do so *after* dropping/zapping the existing SPTE (if it's shadow-present). While commit a54aa15c6bda3 was right about it being impossible to convert a shadow-present SPTE to an MMIO SPTE due to a _guest_ write, it failed to account for writes to guest memory that are outside the scope of KVM. E.g. if host userspace modifies a shadowed gPTE to switch from a memslot to emulted MMIO and then the guest hits a relevant page fault, KVM will install the MMIO SPTE without first zapping the shadow-present SPTE. ------------[ cut here ]------------ is_shadow_present_pte(*sptep) WARNING: arch/x86/kvm/mmu/mmu.c:484 at mark_mmio_spte+0xb2/0xc0 [kvm], CPU#0: vmx_ept_stale_r/4292 Modules linked in: kvm_intel kvm irqbypass CPU: 0 UID: 1000 PID: 4292 Comm: vmx_ept_stale_r Not tainted 7.0.0-rc2-eafebd2d2ab0-sink-vm #319 PREEMPT Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:mark_mmio_spte+0xb2/0xc0 [kvm] Call Trace: <TASK> mmu_set_spte+0x237/0x440 [kvm] ept_page_fault+0x535/0x7f0 [kvm] kvm_mmu_do_page_fault+0xee/0x1f0 [kvm] kvm_mmu_page_fault+0x8d/0x620 [kvm] vmx_handle_exit+0x18c/0x5a0 [kvm_intel] kvm_arch_vcpu_ioctl_run+0xc55/0x1c20 [kvm] kvm_vcpu_ioctl+0x2d5/0x980 [kvm] __x64_sys_ioctl+0x8a/0xd0 do_syscall_64+0xb5/0x730 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x47fa3f </TASK> ---[ end trace 0000000000000000 ]---
- CVSS
- 8.1 HIGH (v3.1, CISA ADP)CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
- Weakness (CWE)
- CWE-416
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- Linux
- NVD analysis
- Modified
- Record last updated
- Jul 14, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Linux Linux linux:linux (from the name) | from a54aa15c6bda3ca7e2f9e040ba968a1da303e24f before 20656cd1f243d3a154aac5dd1b823110b6906fe1; from a54aa15c6bda3ca7e2f9e040ba968a1da303e24f before ed5909992f344a7d3f4024261e9f751d9618a27d; from a54aa15c6bda3ca7e2f9e040ba968a1da303e24f before fd28c5618699180cd69619801e9ae6a5266c0a22; from a54aa15c6bda3ca7e2f9e040ba968a1da303e24f before 459158151a158a6703b49f3c9de0e536d8bd553f; from a54aa15c6bda3ca7e2f9e040ba968a1da303e24f before 695320de6eadb75aaed8be1787c4ce4c189e4c7b; from a54aa15c6bda3ca7e2f9e040ba968a1da303e24f before bce7fe59d43531623f3e43779127bfb33804925d; from a54aa15c6bda3ca7e2f9e040ba968a1da303e24f before aad885e774966e97b675dfe928da164214a71605 | CNA record |
Red Hat Red Hat Enterprise Linux 10 redhat:enterprise_linux | from 0:6.12.0-211.16.1.el10_2 not affected | CISA ADP |
Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support redhat:enterprise_linux_eus | from 0:6.12.0-55.72.1.el10_0 not affected | CISA ADP |
from 0:4.18.0-372.191.1.el8_6 not affected | CISA ADP | |
from 0:4.18.0-372.191.1.el8_6 not affected | CISA ADP | |
from 0:4.18.0-372.191.1.el8_6 not affected | CISA ADP | |
Red Hat Red Hat Enterprise Linux 9.4 Extended Update Support redhat:rhel_eus | from 0:5.14.0-427.124.1.el9_4 not affected | CISA ADP |
linux linux_kernel linux:linux_kernel | from 5.13.1 before 5.15.203; from 5.16 before 6.1.168; from 6.2 before 6.6.131; from 6.7 before 6.12.80; from 6.13 before 6.18.21; from 6.19 before 6.19.11; 5.13; 7.0; and 6 more ranges | NVD |
References
- https://git.kernel.org/stable/c/20656cd1f243d3a154aac5dd1b823110b6906fe1patch
- https://git.kernel.org/stable/c/ed5909992f344a7d3f4024261e9f751d9618a27dpatch
- https://git.kernel.org/stable/c/fd28c5618699180cd69619801e9ae6a5266c0a22patch
- https://git.kernel.org/stable/c/459158151a158a6703b49f3c9de0e536d8bd553fpatch
- https://git.kernel.org/stable/c/695320de6eadb75aaed8be1787c4ce4c189e4c7bpatch
- https://git.kernel.org/stable/c/bce7fe59d43531623f3e43779127bfb33804925dpatch
- https://git.kernel.org/stable/c/aad885e774966e97b675dfe928da164214a71605patch
- https://access.redhat.com/errata/RHSA-2026:13577
- https://access.redhat.com/errata/RHSA-2026:13578
- https://access.redhat.com/errata/RHSA-2026:13932
- https://access.redhat.com/errata/RHSA-2026:13936
- https://access.redhat.com/errata/RHSA-2026:14137
- https://access.redhat.com/errata/RHSA-2026:14230
- https://access.redhat.com/errata/RHSA-2026:14339
- https://access.redhat.com/errata/RHSA-2026:15883
- https://access.redhat.com/errata/RHSA-2026:19521
- https://access.redhat.com/errata/RHSA-2026:19568
- https://access.redhat.com/errata/RHSA-2026:19569
- https://access.redhat.com/errata/RHSA-2026:19875
- https://access.redhat.com/errata/RHSA-2026:20593
- https://access.redhat.com/errata/RHSA-2026:36530
- https://access.redhat.com/errata/RHSA-2026:36531
- https://access.redhat.com/errata/RHSA-2026:36532
- https://access.redhat.com/errata/RHSA-2026:36533
- https://access.redhat.com/errata/RHSA-2026:36534
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.