Linux Kernel up to 6.12.112/6.18.55/7.2.9/7.3-rc5 KVM MMU __kvm_mmu_invalidate_addr null pointer dereference

| CVSS Meta Temp Score | Current Exploit Price (≈) | CTI Interest Score |
|---|---|---|
| 4.7 | $0-$5k | 0.47 |
Summary
A vulnerability was found in Linux Kernel up to 6.12.112/6.18.55/7.2.9/7.3-rc5. It has been rated as problematic. This issue affects the function __kvm_mmu_invalidate_addr of the component KVM MMU. Performing a manipulation results in null pointer dereference.
This vulnerability was named CVE-2026-98717. The attack may be initiated remotely. There is no available exploit.
Upgrading the affected component is advised.
Details
A vulnerability was found in Linux Kernel up to 6.12.112/6.18.55/7.2.9/7.3-rc5. It has been classified as problematic. This affects the function __kvm_mmu_invalidate_addr of the component KVM MMU. The manipulation with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on availability. The summary by CVE is:
In the Linux kernel, the following vulnerability has been resolved: KVM: x86/mmu: Bail from shadow walks if the root is invalid or a dummy When walking shadow page tables, immediately terminate the walk if the root is a "dummy" root, i.e. a root whose top-level page table is backed by the zero page, but otherwise doesn't exist. If memslot creation races with a stage-2 page fault (EPT violation or #NPF) from L2, then if the stars align, KVM will attempt to walk shadow page tables using the zero page and hit a NULL pointer deref. BUG: kernel NULL pointer dereference, address: 0000000000000021 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: Oops: 0000 [#1] SMP CPU: 30 UID: 1000 PID: 941 Comm: qemu Not tainted 7.2.0-rc2-1b731e5ded48-next-vm #1741 PREEMPTLAZY Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:__kvm_mmu_invalidate_addr+0xea/0x210 [kvm] Call Trace: <TASK> kvm_mmu_invalidate_addr+0x92/0xe0 [kvm] __kvm_inject_emulated_page_fault+0x67/0x80 [kvm] ept_page_fault+0x160/0x850 [kvm] kvm_mmu_do_page_fault+0x102/0x1f0 [kvm] kvm_mmu_page_fault+0x8e/0x6b0 [kvm] vmx_handle_exit+0x163/0x640 [kvm_intel] kvm_arch_vcpu_ioctl_run+0x960/0x2120 [kvm] kvm_vcpu_ioctl+0x2c7/0x970 [kvm] __x64_sys_ioctl+0x90/0xd0 do_syscall_64+0x67/0x5f0 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x7f606d0b53bb Opportunistically harden the shadow walks against fully invalid roots, but WARN, as all callers are expected/required to pre-check for a valid root. Don't WARN in the dummy root case as the whole point of using a dummy root is to provide a root that's valid enough to enter the guest, i.e. it should Just Work for all flows except those that *need* to know about dummy roots. Alternatively, KVM could allocate a dedicated page and associated shadow page structure for the dummy root, which is very tempting as it such an approach should be more resilient against unexpected behavior. But that would be a much larger and thus riskier change than simply terminating walks of dummy roots.
The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2026-98717 since 09/25/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. Additional levels of successful authentication are necessary for exploitation. Technical details are known, but no exploit is available.
Upgrading to version 6.12.113, 6.18.56, 7.2.10 or 7.3-rc6 eliminates this vulnerability. Applying the patch e1bcabc07efd029ab414894127411129ffdb8b48/97c1dcce17ef27853860c781f9912257e6adbf7c/681e31f03ec9219099a66a0f6e1bc48e1b5aa914/b6249c1d5665098c8bf12f8d3e4712bf04c775bc is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Product
Type
Vendor
Name
Version
- 6.12.112
- 6.18.0
- 6.18.1
- 6.18.2
- 6.18.3
- 6.18.4
- 6.18.5
- 6.18.6
- 6.18.7
- 6.18.8
- 6.18.9
- 6.18.10
- 6.18.11
- 6.18.12
- 6.18.13
- 6.18.14
- 6.18.15
- 6.18.16
- 6.18.17
- 6.18.18
- 6.18.19
- 6.18.20
- 6.18.21
- 6.18.22
- 6.18.23
- 6.18.24
- 6.18.25
- 6.18.26
- 6.18.27
- 6.18.28
- 6.18.29
- 6.18.30
- 6.18.31
- 6.18.32
- 6.18.33
- 6.18.34
- 6.18.35
- 6.18.36
- 6.18.37
- 6.18.38
- 6.18.39
- 6.18.40
- 6.18.41
- 6.18.42
- 6.18.43
- 6.18.44
- 6.18.45
- 6.18.46
- 6.18.47
- 6.18.48
- 6.18.49
- 6.18.50
- 6.18.51
- 6.18.52
- 6.18.53
- 6.18.54
- 6.18.55
- 7.2.0
- 7.2.1
- 7.2.2
- 7.2.3
- 7.2.4
- 7.2.5
- 7.2.6
- 7.2.7
- 7.2.8
- 7.2.9
- 7.3-rc1
- 7.3-rc2
- 7.3-rc3
- 7.3-rc4
- 7.3-rc5
License
Website
- Vendor: https://www.kernel.org/
CPE 2.3
CPE 2.2
CVSSv4
VulDB Vector: 🔒VulDB Reliability: 🔍
CVSSv3
VulDB Meta Base Score: 4.9VulDB Meta Temp Score: 4.7
VulDB Base Score: 4.9
VulDB Temp Score: 4.7
VulDB Vector: 🔒
VulDB Reliability: 🔍
CVSSv2
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍
Exploiting
Class: Null pointer dereferenceCWE: CWE-476 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒
Physical: No
Local: No
Remote: Yes
Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒
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Threat Intelligence
Interest: 🔍Active Actors: 🔍
Active APT Groups: 🔍
Countermeasures
Recommended: UpgradeStatus: 🔍
0-Day Time: 🔒
Upgrade: Kernel 6.12.113/6.18.56/7.2.10/7.3-rc6
Patch: e1bcabc07efd029ab414894127411129ffdb8b48/97c1dcce17ef27853860c781f9912257e6adbf7c/681e31f03ec9219099a66a0f6e1bc48e1b5aa914/b6249c1d5665098c8bf12f8d3e4712bf04c775bc
Timeline
09/25/2026 CVE reserved10/18/2026 Advisory disclosed
10/18/2026 VulDB entry created
10/18/2026 VulDB entry last update
Sources
Vendor: kernel.orgAdvisory: git.kernel.org
Status: Confirmed
CVE: CVE-2026-98717 (🔒)
GCVE (CVE): GCVE-0-2026-98717
GCVE (VulDB): GCVE-100-421953
Entry
Created: 10/18/2026 19:29Changes: 10/18/2026 19:29 (59)
Complete: 🔍
Cache ID: 216::103
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
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