What is CVE-2026-98283?

CVE-2026-98283 is a High severity Linux kernel vulnerability with a CVSS score of 8.8 out of 10, affecting Linux kernel versions from 4.20 onward and patched in 6.1.189, 6.6.158, 6.12.112 and others. CVE-2026-98283 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-98283?

CVE-2026-98283 has a CVSS score of 8.8 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.

Is there a patch available for CVE-2026-98283?

Yes, CVE-2026-98283 has been patched. Fixed versions include 6.1.189, 6.6.158, 6.12.112 and others. If you are running Linux kernel 4.20 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-98283 actively exploited?

CVE-2026-98283 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-98283

High

In the Linux kernel, the following vulnerability has been resolved: KVM: PPC: Book3S HV: fix use-after-free in kvmhv_emulate_tlbie_all_lpid() kvmhv_emulate_tlbie_all_lpid() iterates the nested-guest IDR and drops mmu_lock before calling kvmhv_emulate_tlbie_lpid(), but does not hold a reference on the kvm_nested_guest pointer obtained from the IDR. A concurrent vCPU issuing a single-LPID tlbie (is=2, ric=2) can race through kvmhv_flush_nested() -> kvmhv_remove_nested() -> idr_remove / --refcnt -> kvmhv_release_nested() -> kfree(gp) in that window, leaving the iterating vCPU with a dangling pointer. The subsequent mutex_lock(&gp->tlb_lock) and accesses to gp->shadow_pgtable, gp->shadow_lpid and gp->l1_host all touch freed memory. The free path is fully L1-controlled. Fix this by incrementing gp->refcnt inside the loop before dropping mmu_lock, mirroring what kvmhv_get_nested() does, and releasing the reference with kvmhv_put_nested() after the per-guest work completes. This is the same get/put discipline already used at every other call site that drops mmu_lock while holding a nested-guest pointer.

Package Linux Kernel

Published 2026-10-06

Last modified 2026-10-07

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

8.8

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Changed

Confidentiality

High

Integrity

High

Availability

High

Vector string

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Affected versions

Linux kernel versions 4.20 and later are affected. Fixed in 6.1.189, 6.6.158, 6.12.112, 6.18.54, 7.2.8, 7.3-rc4 and their respective stable series.

Affected from

≥ 4.20

Fixed in

✓ 6.1.189 6.1.x ✓ 6.6.158 6.6.x ✓ 6.12.112 6.12.x ✓ 6.18.54 6.18.x ✓ 7.2.8 7.2.x ✓ 7.3-rc4

References

6 total

Showing 5 of 6 references View all on NVD

Details

CVE ID CVE-2026-98283

Severity High

CVSS score 8.8 / 10

CVSS version 3.1

Published 2026-10-06

Modified 2026-10-07

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-98283?

CVE-2026-98283 is a High severity Linux kernel vulnerability with a CVSS score of 8.8 out of 10 . It affects Linux kernel versions from 4.20 onward and has been patched in 6.1.189, 6.6.158, 6.12.112 and others. CVE-2026-98283 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-98283?

CVE-2026-98283 has a CVSS score of 8.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.
Is there a patch available for CVE-2026-98283?

Yes. CVE-2026-98283 has been patched. Fixed versions include 6.1.189, 6.6.158, 6.12.112 and others. If you are running Linux kernel 4.20 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-98283 actively exploited?

No. CVE-2026-98283 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.