Vulnerability-Lookup

GHSA-R3WW-97X6-6H4V

Vulnerability from github – Published: 2026-04-01 09:31 – Updated: 2026-04-24 15:32

Details

In the Linux kernel, the following vulnerability has been resolved:

KVM: x86/mmu: Only WARN in direct MMUs when overwriting shadow-present SPTE

Adjust KVM's sanity check against overwriting a shadow-present SPTE with a another SPTE with a different target PFN to only apply to direct MMUs, i.e. only to MMUs without shadowed gPTEs. While it's impossible for KVM to overwrite a shadow-present SPTE in response to a guest write, writes from outside the scope of KVM, e.g. from host userspace, aren't detected by KVM's write tracking and so can break KVM's shadow paging rules.

------------[ cut here ]------------ pfn != spte_to_pfn(*sptep) WARNING: arch/x86/kvm/mmu/mmu.c:3069 at mmu_set_spte+0x1e4/0x440 [kvm], CPU#0: vmx_ept_stale_r/872 Modules linked in: kvm_intel kvm irqbypass CPU: 0 UID: 1000 PID: 872 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:mmu_set_spte+0x1e4/0x440 [kvm] Call Trace: 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 ---[ end trace 0000000000000000 ]---

Severity ?

5.5 (Medium)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2026-23402"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-04-01T09:16:15Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: x86/mmu: Only WARN in direct MMUs when overwriting shadow-present SPTE\n\nAdjust KVM\u0027s sanity check against overwriting a shadow-present SPTE with a\nanother SPTE with a different target PFN to only apply to direct MMUs,\ni.e. only to MMUs without shadowed gPTEs.  While it\u0027s impossible for KVM\nto overwrite a shadow-present SPTE in response to a guest write, writes\nfrom outside the scope of KVM, e.g. from host userspace, aren\u0027t detected\nby KVM\u0027s write tracking and so can break KVM\u0027s shadow paging rules.\n\n  ------------[ cut here ]------------\n  pfn != spte_to_pfn(*sptep)\n  WARNING: arch/x86/kvm/mmu/mmu.c:3069 at mmu_set_spte+0x1e4/0x440 [kvm], CPU#0: vmx_ept_stale_r/872\n  Modules linked in: kvm_intel kvm irqbypass\n  CPU: 0 UID: 1000 PID: 872 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:mmu_set_spte+0x1e4/0x440 [kvm]\n  Call Trace:\n   \u003cTASK\u003e\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   \u003c/TASK\u003e\n  ---[ end trace 0000000000000000 ]---",
  "id": "GHSA-r3ww-97x6-6h4v",
  "modified": "2026-04-24T15:32:20Z",
  "published": "2026-04-01T09:31:27Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-23402"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a1e0f7150639bc30a8e75476d1c7daab77d44992"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/bab090e8fd5607f77379ea78b9d0c683cb1538a9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/df83746075778958954aa0460cca55f4b3fc9c02"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-23402 (GCVE-0-2026-23402)

Vulnerability from cvelistv5 – Published: 2026-04-01 08:36 – Updated: 2026-04-13 06:06

Title

KVM: x86/mmu: Only WARN in direct MMUs when overwriting shadow-present SPTE

Summary

In the Linux kernel, the following vulnerability has been resolved: KVM: x86/mmu: Only WARN in direct MMUs when overwriting shadow-present SPTE Adjust KVM's sanity check against overwriting a shadow-present SPTE with a another SPTE with a different target PFN to only apply to direct MMUs, i.e. only to MMUs without shadowed gPTEs. While it's impossible for KVM to overwrite a shadow-present SPTE in response to a guest write, writes from outside the scope of KVM, e.g. from host userspace, aren't detected by KVM's write tracking and so can break KVM's shadow paging rules. ------------[ cut here ]------------ pfn != spte_to_pfn(*sptep) WARNING: arch/x86/kvm/mmu/mmu.c:3069 at mmu_set_spte+0x1e4/0x440 [kvm], CPU#0: vmx_ept_stale_r/872 Modules linked in: kvm_intel kvm irqbypass CPU: 0 UID: 1000 PID: 872 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:mmu_set_spte+0x1e4/0x440 [kvm] Call Trace: <TASK> 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 </TASK> ---[ end trace 0000000000000000 ]---

Severity ?

No CVSS data available.

Assigner

Linux

References

URL

Tags

	https://git.kernel.org/stable/c/bab090e8fd5607f77…
	https://git.kernel.org/stable/c/a1e0f7150639bc30a…
	https://git.kernel.org/stable/c/df837460757789589…

Impacted products

Vendor

Product

Version

Linux

Affected: 11d45175111d933c5175acc28e56af2213dd5cd6 , < bab090e8fd5607f77379ea78b9d0c683cb1538a9 (git)
Affected: 11d45175111d933c5175acc28e56af2213dd5cd6 , < a1e0f7150639bc30a8e75476d1c7daab77d44992 (git)
Affected: 11d45175111d933c5175acc28e56af2213dd5cd6 , < df83746075778958954aa0460cca55f4b3fc9c02 (git)

Linux

Affected: 6.16
Unaffected: 0 , < 6.16 (semver)
Unaffected: 6.18.21 , ≤ 6.18.* (semver)
Unaffected: 6.19.11 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/x86/kvm/mmu/mmu.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "bab090e8fd5607f77379ea78b9d0c683cb1538a9",
              "status": "affected",
              "version": "11d45175111d933c5175acc28e56af2213dd5cd6",
              "versionType": "git"
            },
            {
              "lessThan": "a1e0f7150639bc30a8e75476d1c7daab77d44992",
              "status": "affected",
              "version": "11d45175111d933c5175acc28e56af2213dd5cd6",
              "versionType": "git"
            },
            {
              "lessThan": "df83746075778958954aa0460cca55f4b3fc9c02",
              "status": "affected",
              "version": "11d45175111d933c5175acc28e56af2213dd5cd6",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "arch/x86/kvm/mmu/mmu.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.16"
            },
            {
              "lessThan": "6.16",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.21",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.21",
                  "versionStartIncluding": "6.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.11",
                  "versionStartIncluding": "6.16",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0",
                  "versionStartIncluding": "6.16",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: x86/mmu: Only WARN in direct MMUs when overwriting shadow-present SPTE\n\nAdjust KVM\u0027s sanity check against overwriting a shadow-present SPTE with a\nanother SPTE with a different target PFN to only apply to direct MMUs,\ni.e. only to MMUs without shadowed gPTEs.  While it\u0027s impossible for KVM\nto overwrite a shadow-present SPTE in response to a guest write, writes\nfrom outside the scope of KVM, e.g. from host userspace, aren\u0027t detected\nby KVM\u0027s write tracking and so can break KVM\u0027s shadow paging rules.\n\n  ------------[ cut here ]------------\n  pfn != spte_to_pfn(*sptep)\n  WARNING: arch/x86/kvm/mmu/mmu.c:3069 at mmu_set_spte+0x1e4/0x440 [kvm], CPU#0: vmx_ept_stale_r/872\n  Modules linked in: kvm_intel kvm irqbypass\n  CPU: 0 UID: 1000 PID: 872 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:mmu_set_spte+0x1e4/0x440 [kvm]\n  Call Trace:\n   \u003cTASK\u003e\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   \u003c/TASK\u003e\n  ---[ end trace 0000000000000000 ]---"
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-13T06:06:44.098Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/bab090e8fd5607f77379ea78b9d0c683cb1538a9"
        },
        {
          "url": "https://git.kernel.org/stable/c/a1e0f7150639bc30a8e75476d1c7daab77d44992"
        },
        {
          "url": "https://git.kernel.org/stable/c/df83746075778958954aa0460cca55f4b3fc9c02"
        }
      ],
      "title": "KVM: x86/mmu: Only WARN in direct MMUs when overwriting shadow-present SPTE",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-23402",
    "datePublished": "2026-04-01T08:36:33.366Z",
    "dateReserved": "2026-01-13T15:37:46.012Z",
    "dateUpdated": "2026-04-13T06:06:44.098Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-R3WW-97X6-6H4V

CVE-2026-23402 (GCVE-0-2026-23402)

Tags

Sightings

Nomenclature