What is CVE-2026-23067?

CVE-2026-23067 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10, affecting Linux kernel versions from 6.16 onward and patched in 6.18.8 and 6.19. CVE-2026-23067 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-23067?

CVE-2026-23067 has a CVSS score of 5.5 out of 10, rated Medium severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Is there a patch available for CVE-2026-23067?

Yes, CVE-2026-23067 has been patched. Fixed versions include 6.18.8 and 6.19. If you are running Linux kernel 6.16 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-23067 actively exploited?

CVE-2026-23067 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-23067

Medium

In the Linux kernel, the following vulnerability has been resolved: iommu/io-pgtable-arm: fix size_t signedness bug in unmap path __arm_lpae_unmap() returns size_t but was returning -ENOENT (negative error code) when encountering an unmapped PTE. Since size_t is unsigned, -ENOENT (typically -2) becomes a huge positive value (0xFFFFFFFFFFFFFFFE on 64-bit systems). This corrupted value propagates through the call chain: __arm_lpae_unmap() returns -ENOENT as size_t -> arm_lpae_unmap_pages() returns it -> __iommu_unmap() adds it to iova address -> iommu_pgsize() triggers BUG_ON due to corrupted iova This can cause IOVA address overflow in __iommu_unmap() loop and trigger BUG_ON in iommu_pgsize() from invalid address alignment. Fix by returning 0 instead of -ENOENT. The WARN_ON already signals the error condition, and returning 0 (meaning "nothing unmapped") is the correct semantic for size_t return type. This matches the behavior of other io-pgtable implementations (io-pgtable-arm-v7s, io-pgtable-dart) which return 0 on error conditions.

Package Linux Kernel

Published 2026-02-04

Last modified 2026-03-13

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

5.5

out of 10

Medium

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

High

Vector string

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

Weakness type

CWE-617

CVE-2026-23067 is classified as CWE-617

See CWE-617 on MITRE CWE for full details on this weakness type.

Affected versions

Linux kernel versions 6.16 and later are affected. Fixed in 6.18.8, 6.19 and their respective stable series.

Affected from

≥ 6.16

Fixed in

✓ 6.18.8 6.18.x ✓ 6.19

References

The following references provide additional information about CVE-2026-23067 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Kernel patch commit
https://git.kernel.org/stable/c/374e7af67d9d9d6103c2cfc8eb32abfecf3a2fd8
Patch
Kernel patch commit
https://git.kernel.org/stable/c/41ec6988547819756fb65e94fc24f3e0dddf84ac
Patch

Details

CVE ID CVE-2026-23067

Severity Medium

CVSS score 5.5 / 10

CVSS version 3.1

Published 2026-02-04

Modified 2026-03-13

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-23067?

CVE-2026-23067 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 . It affects Linux kernel versions from 6.16 onward and has been patched in 6.18.8 and 6.19. CVE-2026-23067 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-23067?

CVE-2026-23067 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
Is there a patch available for CVE-2026-23067?

Yes — CVE-2026-23067 has been patched. Fixed versions include 6.18.8 and 6.19. If you are running Linux kernel 6.16 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-23067 actively exploited?

No — CVE-2026-23067 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.