CVE-2026-98720 (GCVE-0-2026-98720)

Vulnerability from cvelistv5 – Published: 2026-10-18 15:46 – Updated: 2026-10-19 09:24
VLAI
Title
KVM: nVMX: Force MSR bitmap refresh if runtime eVMCS controls are modified
Summary
In the Linux kernel, the following vulnerability has been resolved: KVM: nVMX: Force MSR bitmap refresh if runtime eVMCS controls are modified Force a refresh of the vmcs02 MSR bitmap during nested VM-Enter if the runtime eVMCS controls (pin, primary, secondary, etc.) are being updated. If L1 isn't intercepting TPR writes, runs L2 with TPR virtualization, and then runs the same L2 with TPR virtualization disabled, KVM will fail to refresh msr_bitmap02 and leave TPR in passthrough mode even though TPR virtualization is disabled. I.e. failure to refresh the bitmap lets L2 (or L1 by proxy) read and write L0's TPR.
Severity
No CVSS data available.
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6848 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e , < 2db11598b59f16ddb6420693f9a4ac4efc3d4789 (git)
Affected: 502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e , < f6189e26d0237e47e2f04f9cb1e43fd19a9b2f3a (git)
Affected: 502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e , < 1e497e3bdab6983deb68a1d26b488027deb4527f (git)
Affected: 502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e , < 2abb25273c82061dd4670690c81c319c03740bf6 (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.17
Unaffected: 0 , < 5.17 (semver)
Unaffected: 6.12.113 , ≤ 6.12.* (semver)
Unaffected: 6.18.56 , ≤ 6.18.* (semver)
Unaffected: 7.2.10 , ≤ 7.2.* (semver)
Unaffected: 7.3 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "arch/x86/kvm/vmx/nested.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "2db11598b59f16ddb6420693f9a4ac4efc3d4789",
              "status": "affected",
              "version": "502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e",
              "versionType": "git"
            },
            {
              "lessThan": "f6189e26d0237e47e2f04f9cb1e43fd19a9b2f3a",
              "status": "affected",
              "version": "502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e",
              "versionType": "git"
            },
            {
              "lessThan": "1e497e3bdab6983deb68a1d26b488027deb4527f",
              "status": "affected",
              "version": "502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e",
              "versionType": "git"
            },
            {
              "lessThan": "2abb25273c82061dd4670690c81c319c03740bf6",
              "status": "affected",
              "version": "502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "arch/x86/kvm/vmx/nested.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.17"
            },
            {
              "lessThan": "5.17",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.113",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.56",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.10",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.113",
                  "versionStartIncluding": "5.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.56",
                  "versionStartIncluding": "5.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2.10",
                  "versionStartIncluding": "5.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.3",
                  "versionStartIncluding": "5.17",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: nVMX: Force MSR bitmap refresh if runtime eVMCS controls are modified\n\nForce a refresh of the vmcs02 MSR bitmap during nested VM-Enter if the\nruntime eVMCS controls (pin, primary, secondary, etc.) are being updated.\nIf L1 isn\u0027t intercepting TPR writes, runs L2 with TPR virtualization, and\nthen runs the same L2 with TPR virtualization disabled, KVM will fail to\nrefresh msr_bitmap02 and leave TPR in passthrough mode even though TPR\nvirtualization is disabled.  I.e. failure to refresh the bitmap lets L2 (or\nL1 by proxy) read and write L0\u0027s TPR."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-19T09:24:31.090Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/2db11598b59f16ddb6420693f9a4ac4efc3d4789"
        },
        {
          "url": "https://git.kernel.org/stable/c/f6189e26d0237e47e2f04f9cb1e43fd19a9b2f3a"
        },
        {
          "url": "https://git.kernel.org/stable/c/1e497e3bdab6983deb68a1d26b488027deb4527f"
        },
        {
          "url": "https://git.kernel.org/stable/c/2abb25273c82061dd4670690c81c319c03740bf6"
        }
      ],
      "title": "KVM: nVMX: Force MSR bitmap refresh if runtime eVMCS controls are modified",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-98720",
    "datePublished": "2026-10-18T15:46:55.863Z",
    "dateReserved": "2026-09-25T10:25:14.366Z",
    "dateUpdated": "2026-10-19T09:24:31.090Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-98720",
      "date": "2026-11-03",
      "epss": "0.00168",
      "percentile": "0.06059"
    },
    "microsoft_vex": {
      "current_release_date": "2026-11-01T14:48:57.000Z",
      "cve": "CVE-2026-98720",
      "id": "msrc_CVE-2026-98720",
      "initial_release_date": "2026-10-20T01:04:29.000Z",
      "product_status:known_affected": "2",
      "product_status:under_investigation": "1",
      "source": "Microsoft CSAF VEX",
      "status": "final",
      "title": "KVM: nVMX: Force MSR bitmap refresh if runtime eVMCS controls are modified",
      "url": "https://msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-98720.json",
      "version": "3"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "arch/x86/kvm/vmx/nested.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "2db11598b59f16ddb6420693f9a4ac4efc3d4789",
                    "status": "affected",
                    "version": "502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "f6189e26d0237e47e2f04f9cb1e43fd19a9b2f3a",
                    "status": "affected",
                    "version": "502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "1e497e3bdab6983deb68a1d26b488027deb4527f",
                    "status": "affected",
                    "version": "502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "2abb25273c82061dd4670690c81c319c03740bf6",
                    "status": "affected",
                    "version": "502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e",
                    "versionType": "git"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "arch/x86/kvm/vmx/nested.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "5.17"
                  },
                  {
                    "lessThan": "5.17",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.12.*",
                    "status": "unaffected",
                    "version": "6.12.113",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.18.*",
                    "status": "unaffected",
                    "version": "6.18.56",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "7.2.*",
                    "status": "unaffected",
                    "version": "7.2.10",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "7.3",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: nVMX: Force MSR bitmap refresh if runtime eVMCS controls are modified\n\nForce a refresh of the vmcs02 MSR bitmap during nested VM-Enter if the\nruntime eVMCS controls (pin, primary, secondary, etc.) are being updated.\nIf L1 isn\u0027t intercepting TPR writes, runs L2 with TPR virtualization, and\nthen runs the same L2 with TPR virtualization disabled, KVM will fail to\nrefresh msr_bitmap02 and leave TPR in passthrough mode even though TPR\nvirtualization is disabled.  I.e. failure to refresh the bitmap lets L2 (or\nL1 by proxy) read and write L0\u0027s TPR."
          }
        ],
        "id": "CVE-2026-98720",
        "lastModified": "2026-10-19T10:19:36.230",
        "metrics": {},
        "published": "2026-10-18T16:17:25.583",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/1e497e3bdab6983deb68a1d26b488027deb4527f"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/2abb25273c82061dd4670690c81c319c03740bf6"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/2db11598b59f16ddb6420693f9a4ac4efc3d4789"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "url": "https://git.kernel.org/stable/c/f6189e26d0237e47e2f04f9cb1e43fd19a9b2f3a"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Received"
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-10-22T21:09:43+00:00",
      "cve": "CVE-2026-98720",
      "id": "CVE-2026-98720",
      "initial_release_date": "2026-10-18T00:00:00+00:00",
      "product_status:known_affected": "235",
      "product_status:known_not_affected": "43",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: KVM: nVMX: Force MSR bitmap refresh if runtime eVMCS controls are modified",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98720.json",
      "version": "3"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

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.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON

Loading timeline…




    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.