CVE-2026-98717

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-98717", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.366Z", "datePublished": "2026-10-18T15:46:51.862Z", "dateUpdated": "2026-10-21T12:56:02.536Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-21T12:56:02.536Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: x86/mmu: Bail from shadow walks if the root is invalid or a dummy\n\nWhen walking shadow page tables, immediately terminate the walk if the root\nis a \"dummy\" root, i.e. a root whose top-level page table is backed by the\nzero page, but otherwise doesn't exist. If memslot creation races with a\nstage-2 page fault (EPT violation or #NPF) from L2, then if the stars align,\nKVM will attempt to walk shadow page tables using the zero page and hit a\nNULL pointer deref.\n\n BUG: kernel NULL pointer dereference, address: 0000000000000021\n #PF: supervisor read access in kernel mode\n #PF: error_code(0x0000) - not-present page\n PGD 0 P4D 0\n Oops: Oops: 0000 [#1] SMP\n CPU: 30 UID: 1000 PID: 941 Comm: qemu Not tainted 7.2.0-rc2-1b731e5ded48-next-vm #1741 PREEMPTLAZY\n Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015\n RIP: 0010:__kvm_mmu_invalidate_addr+0xea/0x210 [kvm]\n Call Trace:\n <TASK>\n kvm_mmu_invalidate_addr+0x92/0xe0 [kvm]\n __kvm_inject_emulated_page_fault+0x67/0x80 [kvm]\n ept_page_fault+0x160/0x850 [kvm]\n kvm_mmu_do_page_fault+0x102/0x1f0 [kvm]\n kvm_mmu_page_fault+0x8e/0x6b0 [kvm]\n vmx_handle_exit+0x163/0x640 [kvm_intel]\n kvm_arch_vcpu_ioctl_run+0x960/0x2120 [kvm]\n kvm_vcpu_ioctl+0x2c7/0x970 [kvm]\n __x64_sys_ioctl+0x90/0xd0\n do_syscall_64+0x67/0x5f0\n entry_SYSCALL_64_after_hwframe+0x4b/0x53\n RIP: 0033:0x7f606d0b53bb\n\nOpportunistically harden the shadow walks against fully invalid roots, but\nWARN, as all callers are expected/required to pre-check for a valid root.\nDon't WARN in the dummy root case as the whole point of using a dummy root\nis to provide a root that's valid enough to enter the guest, i.e. it should\nJust Work for all flows except those that *need* to know about dummy roots.\n\nAlternatively, KVM could allocate a dedicated page and associated shadow\npage structure for the dummy root, which is very tempting as it such an\napproach should be more resilient against unexpected behavior. But that\nwould be a much larger and thus riskier change than simply terminating\nwalks of dummy roots."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["arch/x86/kvm/mmu/mmu.c"], "versions": [{"version": "0e3223d8d00ac05849661f1b8b476d3caca251cf", "lessThan": "951fce1510645ba5df38da6fb85ece5726ec347d", "status": "affected", "versionType": "git"}, {"version": "0e3223d8d00ac05849661f1b8b476d3caca251cf", "lessThan": "e1bcabc07efd029ab414894127411129ffdb8b48", "status": "affected", "versionType": "git"}, {"version": "0e3223d8d00ac05849661f1b8b476d3caca251cf", "lessThan": "97c1dcce17ef27853860c781f9912257e6adbf7c", "status": "affected", "versionType": "git"}, {"version": "0e3223d8d00ac05849661f1b8b476d3caca251cf", "lessThan": "681e31f03ec9219099a66a0f6e1bc48e1b5aa914", "status": "affected", "versionType": "git"}, {"version": "0e3223d8d00ac05849661f1b8b476d3caca251cf", "lessThan": "b6249c1d5665098c8bf12f8d3e4712bf04c775bc", "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/mmu/mmu.c"], "versions": [{"version": "6.6", "status": "affected"}, {"version": "0", "lessThan": "6.6", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.160", "lessThanOrEqual": "6.6.*", "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": "6.6", "versionEndExcluding": "6.6.160"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "6.12.113"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "6.18.56"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "7.2.10"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/951fce1510645ba5df38da6fb85ece5726ec347d"}, {"url": "https://git.kernel.org/stable/c/e1bcabc07efd029ab414894127411129ffdb8b48"}, {"url": "https://git.kernel.org/stable/c/97c1dcce17ef27853860c781f9912257e6adbf7c"}, {"url": "https://git.kernel.org/stable/c/681e31f03ec9219099a66a0f6e1bc48e1b5aa914"}, {"url": "https://git.kernel.org/stable/c/b6249c1d5665098c8bf12f8d3e4712bf04c775bc"}], "title": "KVM: x86/mmu: Bail from shadow walks if the root is invalid or a dummy", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"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": "951fce1510645ba5df38da6fb85ece5726ec347d", "status": "affected", "version": "0e3223d8d00ac05849661f1b8b476d3caca251cf", "versionType": "git"}, {"lessThan": "e1bcabc07efd029ab414894127411129ffdb8b48", "status": "affected", "version": "0e3223d8d00ac05849661f1b8b476d3caca251cf", "versionType": "git"}, {"lessThan": "97c1dcce17ef27853860c781f9912257e6adbf7c", "status": "affected", "version": "0e3223d8d00ac05849661f1b8b476d3caca251cf", "versionType": "git"}, {"lessThan": "681e31f03ec9219099a66a0f6e1bc48e1b5aa914", "status": "affected", "version": "0e3223d8d00ac05849661f1b8b476d3caca251cf", "versionType": "git"}, {"lessThan": "b6249c1d5665098c8bf12f8d3e4712bf04c775bc", "status": "affected", "version": "0e3223d8d00ac05849661f1b8b476d3caca251cf", "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": "6.6"}, {"lessThan": "6.6", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.160", "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: x86/mmu: Bail from shadow walks if the root is invalid or a dummy\n\nWhen walking shadow page tables, immediately terminate the walk if the root\nis a \"dummy\" root, i.e. a root whose top-level page table is backed by the\nzero page, but otherwise doesn't exist. If memslot creation races with a\nstage-2 page fault (EPT violation or #NPF) from L2, then if the stars align,\nKVM will attempt to walk shadow page tables using the zero page and hit a\nNULL pointer deref.\n\n BUG: kernel NULL pointer dereference, address: 0000000000000021\n #PF: supervisor read access in kernel mode\n #PF: error_code(0x0000) - not-present page\n PGD 0 P4D 0\n Oops: Oops: 0000 [#1] SMP\n CPU: 30 UID: 1000 PID: 941 Comm: qemu Not tainted 7.2.0-rc2-1b731e5ded48-next-vm #1741 PREEMPTLAZY\n Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015\n RIP: 0010:__kvm_mmu_invalidate_addr+0xea/0x210 [kvm]\n Call Trace:\n <TASK>\n kvm_mmu_invalidate_addr+0x92/0xe0 [kvm]\n __kvm_inject_emulated_page_fault+0x67/0x80 [kvm]\n ept_page_fault+0x160/0x850 [kvm]\n kvm_mmu_do_page_fault+0x102/0x1f0 [kvm]\n kvm_mmu_page_fault+0x8e/0x6b0 [kvm]\n vmx_handle_exit+0x163/0x640 [kvm_intel]\n kvm_arch_vcpu_ioctl_run+0x960/0x2120 [kvm]\n kvm_vcpu_ioctl+0x2c7/0x970 [kvm]\n __x64_sys_ioctl+0x90/0xd0\n do_syscall_64+0x67/0x5f0\n entry_SYSCALL_64_after_hwframe+0x4b/0x53\n RIP: 0033:0x7f606d0b53bb\n\nOpportunistically harden the shadow walks against fully invalid roots, but\nWARN, as all callers are expected/required to pre-check for a valid root.\nDon't WARN in the dummy root case as the whole point of using a dummy root\nis to provide a root that's valid enough to enter the guest, i.e. it should\nJust Work for all flows except those that *need* to know about dummy roots.\n\nAlternatively, KVM could allocate a dedicated page and associated shadow\npage structure for the dummy root, which is very tempting as it such an\napproach should be more resilient against unexpected behavior. But that\nwould be a much larger and thus riskier change than simply terminating\nwalks of dummy roots."}], "id": "CVE-2026-98717", "lastModified": "2026-10-21T13:21:39.807", "metrics": {}, "published": "2026-10-18T16:17:25.250", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/681e31f03ec9219099a66a0f6e1bc48e1b5aa914"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/951fce1510645ba5df38da6fb85ece5726ec347d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/97c1dcce17ef27853860c781f9912257e6adbf7c"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/b6249c1d5665098c8bf12f8d3e4712bf04c775bc"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/e1bcabc07efd029ab414894127411129ffdb8b48"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: KVM: x86/mmu: Bail from shadow walks if the root is invalid or a dummy", "id": "2555044", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2555044"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.7", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-476", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nKVM: x86/mmu: Bail from shadow walks if the root is invalid or a dummy\nWhen walking shadow page tables, immediately terminate the walk if the root\nis a \"dummy\" root, i.e. a root whose top-level page table is backed by the\nzero page, but otherwise doesn't exist. If memslot creation races with a\nstage-2 page fault (EPT violation or #NPF) from L2, then if the stars align,\nKVM will attempt to walk shadow page tables using the zero page and hit a\nNULL pointer deref.\nBUG: kernel NULL pointer dereference, address: 0000000000000021\n#PF: supervisor read access in kernel mode\n#PF: error_code(0x0000) - not-present page\nPGD 0 P4D 0\nOops: Oops: 0000 [#1] SMP\nCPU: 30 UID: 1000 PID: 941 Comm: qemu Not tainted 7.2.0-rc2-1b731e5ded48-next-vm #1741 PREEMPTLAZY\nHardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015\nRIP: 0010:__kvm_mmu_invalidate_addr+0xea/0x210 [kvm]\nCall Trace:\n<TASK>\nkvm_mmu_invalidate_addr+0x92/0xe0 [kvm]\n__kvm_inject_emulated_page_fault+0x67/0x80 [kvm]\nept_page_fault+0x160/0x850 [kvm]\nkvm_mmu_do_page_fault+0x102/0x1f0 [kvm]\nkvm_mmu_page_fault+0x8e/0x6b0 [kvm]\nvmx_handle_exit+0x163/0x640 [kvm_intel]\nkvm_arch_vcpu_ioctl_run+0x960/0x2120 [kvm]\nkvm_vcpu_ioctl+0x2c7/0x970 [kvm]\n__x64_sys_ioctl+0x90/0xd0\ndo_syscall_64+0x67/0x5f0\nentry_SYSCALL_64_after_hwframe+0x4b/0x53\nRIP: 0033:0x7f606d0b53bb\nOpportunistically harden the shadow walks against fully invalid roots, but\nWARN, as all callers are expected/required to pre-check for a valid root.\nDon't WARN in the dummy root case as the whole point of using a dummy root\nis to provide a root that's valid enough to enter the guest, i.e. it should\nJust Work for all flows except those that *need* to know about dummy roots.\nAlternatively, KVM could allocate a dedicated page and associated shadow\npage structure for the dummy root, which is very tempting as it such an\napproach should be more resilient against unexpected behavior. But that\nwould be a much larger and thus riskier change than simply terminating\nwalks of dummy roots.", "A flaw was found in the Linux kernel's KVM (Kernel-based Virtual Machine) subsystem. This vulnerability allows a local user or guest virtual machine to cause a Denial of Service (DoS) by crashing the host kernel. The issue stems from a race condition between memory slot creation and stage-2 page fault handling, leading the memory management unit to improperly walk invalid shadow page tables and trigger a NULL pointer dereference."], "name": "CVE-2026-98717", "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": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "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": "Not affected", "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-2026-98717\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-98717\nhttps://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98717.mbox"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[0e3223d8d00ac05849661f1b8b476d3caca251cf,e1bcabc07efd029ab414894127411129ffdb8b48)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[0e3223d8d00ac05849661f1b8b476d3caca251cf,97c1dcce17ef27853860c781f9912257e6adbf7c)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[0e3223d8d00ac05849661f1b8b476d3caca251cf,681e31f03ec9219099a66a0f6e1bc48e1b5aa914)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[0e3223d8d00ac05849661f1b8b476d3caca251cf,b6249c1d5665098c8bf12f8d3e4712bf04c775bc)"}}], "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": "6.6"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,6.6)"}}, {"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": "2026-10-18T19:30:14.461845+00:00", "updated": "2026-10-23T06:30:07.431340+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}