CVE-2026-98720

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-98720", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.366Z", "datePublished": "2026-10-18T15:46:55.863Z", "dateUpdated": "2026-10-19T09:24:31.090Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T09:24:31.090Z"}, "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't 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's TPR."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["arch/x86/kvm/vmx/nested.c"], "versions": [{"version": "502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e", "lessThan": "2db11598b59f16ddb6420693f9a4ac4efc3d4789", "status": "affected", "versionType": "git"}, {"version": "502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e", "lessThan": "f6189e26d0237e47e2f04f9cb1e43fd19a9b2f3a", "status": "affected", "versionType": "git"}, {"version": "502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e", "lessThan": "1e497e3bdab6983deb68a1d26b488027deb4527f", "status": "affected", "versionType": "git"}, {"version": "502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e", "lessThan": "2abb25273c82061dd4670690c81c319c03740bf6", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["arch/x86/kvm/vmx/nested.c"], "versions": [{"version": "5.17", "status": "affected"}, {"version": "0", "lessThan": "5.17", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.113", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.56", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.10", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.17", "versionEndExcluding": "6.12.113"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.17", "versionEndExcluding": "6.18.56"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.17", "versionEndExcluding": "7.2.10"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.17", "versionEndExcluding": "7.3"}]}]}], "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"}}}}

{}

{"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't 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's 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"}

{"bugzilla": {"description": "kernel: KVM: nVMX: Force MSR bitmap refresh if runtime eVMCS controls are modified", "id": "2555141", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2555141"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.3", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-270", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nKVM: nVMX: Force MSR bitmap refresh if runtime eVMCS controls are modified\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't 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's TPR.", "A flaw was found in the Linux kernel's KVM (Kernel-based Virtual Machine) nested virtualization implementation. This flaw allows an attacker within a nested guest to bypass isolation boundaries and directly access host hardware controls, potentially causing host system instability or a Denial of Service (DoS). The issue occurs when nested virtualization control settings are modified without refreshing internal register permissions, leaving the host's Task Priority Register (TPR) directly accessible to the guest."], "name": "CVE-2026-98720", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Not affected", "package_name": "openshift/ose-rhel-coreos-8", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Fix deferred", "package_name": "openshift/ose-rhel-coreos-9", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-10-18T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-98720\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-98720\nhttps://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98720.mbox"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e,2db11598b59f16ddb6420693f9a4ac4efc3d4789)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e,f6189e26d0237e47e2f04f9cb1e43fd19a9b2f3a)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e,1e497e3bdab6983deb68a1d26b488027deb4527f)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[502d2bf5f2fd7c05adc2d4f057910bd5d4c4c63e,2abb25273c82061dd4670690c81c319c03740bf6)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "5.17"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,5.17)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.113,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.56,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.10,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3-rc6,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-10-18T19:30:14.461542+00:00", "updated": "2026-10-23T08:45:16.392657+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}