CVE-2026-23402

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> KVM: x86/mmu: Only WARN in direct MMUs when overwriting shadow-present SPTE<br /> <br /> Adjust KVM&amp;#39;s sanity check against overwriting a shadow-present SPTE with a<br /> another SPTE with a different target PFN to only apply to direct MMUs,<br /> i.e. only to MMUs without shadowed gPTEs. While it&amp;#39;s impossible for KVM<br /> to overwrite a shadow-present SPTE in response to a guest write, writes<br /> from outside the scope of KVM, e.g. from host userspace, aren&amp;#39;t detected<br /> by KVM&amp;#39;s write tracking and so can break KVM&amp;#39;s shadow paging rules.<br /> <br /> ------------[ cut here ]------------<br /> pfn != spte_to_pfn(*sptep)<br /> WARNING: arch/x86/kvm/mmu/mmu.c:3069 at mmu_set_spte+0x1e4/0x440 [kvm], CPU#0: vmx_ept_stale_r/872<br /> Modules linked in: kvm_intel kvm irqbypass<br /> CPU: 0 UID: 1000 PID: 872 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:mmu_set_spte+0x1e4/0x440 [kvm]<br /> Call Trace:<br /> <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 /> <br /> ---[ end trace 0000000000000000 ]---