UnratedFix available

KVM: nVMX: Force MSR bitmap refresh if runtime eVMCS controls are modified

Type: advisorySources: OSV

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.

Products: Kernel
Affected versions: Not specified
Fixed versions: 6.12.113, 6.18.56, 7.2.10
CVEs: CVE-2026-98720
Confirmed fixed CVEs: Not specified
Updated in this feed: 7 Nov 2026, 06:57 UTC · Revision 1

Source evidence

KVM: nVMX: Force MSR bitmap refresh if runtime eVMCS controls are modified

core-osv · Original source

Published 18 Oct 2026, 15:46 UTC

osv:CVE-2026-98720

Kernel

Fixed versions: 6.12.113, 6.18.56, 7.2.10

Complete source record

{
  "id": "5d861138382c8e14bbe0c8459a70bd673ad6e7ffcf9b475cc709093b47f61fb2",
  "url": "https://osv.dev/vulnerability/CVE-2026-98720",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "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.",
    "evidence": "osv:CVE-2026-98720",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.12.113",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.56",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.2.10",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-98720",
      "aliases": [
        "CVE-2026-98720"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
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                {
                  "fixed": "2db11598b59f16ddb6420693f9a4ac4efc3d4789"
                },
                {
                  "fixed": "f6189e26d0237e47e2f04f9cb1e43fd19a9b2f3a"
                },
                {
                  "fixed": "1e497e3bdab6983deb68a1d26b488027deb4527f"
                },
                {
                  "fixed": "2abb25273c82061dd4670690c81c319c03740bf6"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98720.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.17.0"
                },
                {
                  "fixed": "6.12.113"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.13.0"
                },
                {
                  "fixed": "6.18.56"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
                },
                {
                  "fixed": "7.2.10"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98720.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:50.002043984Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/1e497e3bdab6983deb68a1d26b488027deb4527f",
        "https://git.kernel.org/stable/c/2abb25273c82061dd4670690c81c319c03740bf6",
        "https://git.kernel.org/stable/c/2db11598b59f16ddb6420693f9a4ac4efc3d4789",
        "https://git.kernel.org/stable/c/f6189e26d0237e47e2f04f9cb1e43fd19a9b2f3a",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98720.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-98720",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98720.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-98720",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 518563,
  "published_at": "2026-10-18T15:46:55.863+00:00"
}