{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2026-23401",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-23401",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-04-01T08:36:32.367Z",
    "updatedAt": "2026-07-15T01:18:42.620Z",
    "importedAt": "2026-10-24T01:58:02.025Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "KVM: x86/mmu: Drop/zap existing present SPTE even when creating an MMIO SPTE",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: x86/mmu: Drop/zap existing present SPTE even when creating an MMIO SPTE\n\nWhen installing an emulated MMIO SPTE, do so *after* dropping/zapping the\nexisting SPTE (if it's shadow-present).  While commit a54aa15c6bda3 was\nright about it being impossible to convert a shadow-present SPTE to an\nMMIO SPTE due to a _guest_ write, it failed to account for writes to guest\nmemory that are outside the scope of KVM.\n\nE.g. if host userspace modifies a shadowed gPTE to switch from a memslot\nto emulted MMIO and then the guest hits a relevant page fault, KVM will\ninstall the MMIO SPTE without first zapping the shadow-present SPTE.\n\n  ------------[ cut here ]------------\n  is_shadow_present_pte(*sptep)\n  WARNING: arch/x86/kvm/mmu/mmu.c:484 at mark_mmio_spte+0xb2/0xc0 [kvm], CPU#0: vmx_ept_stale_r/4292\n  Modules linked in: kvm_intel kvm irqbypass\n  CPU: 0 UID: 1000 PID: 4292 Comm: vmx_ept_stale_r Not tainted 7.0.0-rc2-eafebd2d2ab0-sink-vm #319 PREEMPT\n  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015\n  RIP: 0010:mark_mmio_spte+0xb2/0xc0 [kvm]\n  Call Trace:\n   <TASK>\n   mmu_set_spte+0x237/0x440 [kvm]\n   ept_page_fault+0x535/0x7f0 [kvm]\n   kvm_mmu_do_page_fault+0xee/0x1f0 [kvm]\n   kvm_mmu_page_fault+0x8d/0x620 [kvm]\n   vmx_handle_exit+0x18c/0x5a0 [kvm_intel]\n   kvm_arch_vcpu_ioctl_run+0xc55/0x1c20 [kvm]\n   kvm_vcpu_ioctl+0x2d5/0x980 [kvm]\n   __x64_sys_ioctl+0x8a/0xd0\n   do_syscall_64+0xb5/0x730\n   entry_SYSCALL_64_after_hwframe+0x4b/0x53\n  RIP: 0033:0x47fa3f\n   </TASK>\n  ---[ end trace 0000000000000000 ]---",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "a54aa15c6bda3ca7e2f9e040ba968a1da303e24f",
              "status": "affected",
              "versionType": "git",
              "lessThan": "20656cd1f243d3a154aac5dd1b823110b6906fe1"
            },
            {
              "version": "a54aa15c6bda3ca7e2f9e040ba968a1da303e24f",
              "status": "affected",
              "versionType": "git",
              "lessThan": "ed5909992f344a7d3f4024261e9f751d9618a27d"
            },
            {
              "version": "a54aa15c6bda3ca7e2f9e040ba968a1da303e24f",
              "status": "affected",
              "versionType": "git",
              "lessThan": "fd28c5618699180cd69619801e9ae6a5266c0a22"
            },
            {
              "version": "a54aa15c6bda3ca7e2f9e040ba968a1da303e24f",
              "status": "affected",
              "versionType": "git",
              "lessThan": "459158151a158a6703b49f3c9de0e536d8bd553f"
            },
            {
              "version": "a54aa15c6bda3ca7e2f9e040ba968a1da303e24f",
              "status": "affected",
              "versionType": "git",
              "lessThan": "695320de6eadb75aaed8be1787c4ce4c189e4c7b"
            },
            {
              "version": "a54aa15c6bda3ca7e2f9e040ba968a1da303e24f",
              "status": "affected",
              "versionType": "git",
              "lessThan": "bce7fe59d43531623f3e43779127bfb33804925d"
            },
            {
              "version": "a54aa15c6bda3ca7e2f9e040ba968a1da303e24f",
              "status": "affected",
              "versionType": "git",
              "lessThan": "aad885e774966e97b675dfe928da164214a71605"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "5.13",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "5.13"
            },
            {
              "version": "5.15.203",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "6.1.168",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.6.131",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "version": "6.12.80",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "version": "6.18.21",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "version": "6.19.11",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.19.*"
            },
            {
              "version": "7.0",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}