What is CVE-2026-43166?

CVE-2026-43166 is a High severity Linux kernel vulnerability with a CVSS score of 7.1 out of 10, classified as a Out-of-bounds Write flaw (CWE-787), affecting Linux kernel versions from 6.15 onward and patched in 6.18.16, 6.19.6 and 7.0. CVE-2026-43166 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-43166?

CVE-2026-43166 has a CVSS score of 7.1 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H.

Is there a patch available for CVE-2026-43166?

Yes, CVE-2026-43166 has been patched. Fixed versions include 6.18.16, 6.19.6 and 7.0. If you are running Linux kernel 6.15 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-43166 actively exploited?

CVE-2026-43166 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is Out-of-bounds Write (CWE-787)?

The product writes data past the end or before the beginning of the intended buffer. See MITRE CWE for full details: https://cwe.mitre.org/data/definitions/787.html

CVE-2026-43166

High

In the Linux kernel, the following vulnerability has been resolved: erofs: fix interlaced plain identification for encoded extents Only plain data whose start position and on-disk physical length are both aligned to the block size should be classified as interlaced plain extents. Otherwise, it must be treated as shifted plain extents. This issue was found by syzbot using a crafted compressed image containing plain extents with unaligned physical lengths, which can cause OOB read in z_erofs_transform_plain().

Package Linux Kernel

Published 2026-05-06

Last modified 2026-05-13

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.1

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

High

Vector string

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

Weakness type

CWE-787

CVE-2026-43166 is a Out-of-bounds Write vulnerability

What is Out-of-bounds Write?

The product writes data past the end or before the beginning of the intended buffer. Learn more on MITRE CWE

Affected versions

Linux kernel versions 6.15 and later are affected. Fixed in 6.18.16, 6.19.6, 7.0 and their respective stable series.

Affected from

≥ 6.15

Fixed in

✓ 6.18.16 6.18.x ✓ 6.19.6 6.19.x ✓ 7.0

References

The following references provide additional information about CVE-2026-43166 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/4a2d046e4b13202a6301a993961f5b30ae4d7119
Patch
Kernel patch commit
https://git.kernel.org/stable/c/9d5a97bc71ed5783687705c708454c4453aa91d1
Patch
Kernel patch commit
https://git.kernel.org/stable/c/d3790f26d38606f020212486359b84632c19d08b
Patch

Details

CVE ID CVE-2026-43166

Severity High

CVSS score 7.1 / 10

CVSS version 3.1

Published 2026-05-06

Modified 2026-05-13

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-43166?

CVE-2026-43166 is a High severity Linux kernel vulnerability with a CVSS score of 7.1 out of 10 , classified as an Out-of-bounds Write flaw (CWE-787) . It affects Linux kernel versions from 6.15 onward and has been patched in 6.18.16, 6.19.6 and 7.0. CVE-2026-43166 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-43166?

CVE-2026-43166 has a CVSS score of 7.1 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H.
Is there a patch available for CVE-2026-43166?

Yes — CVE-2026-43166 has been patched. Fixed versions include 6.18.16, 6.19.6 and 7.0. If you are running Linux kernel 6.15 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-43166 actively exploited?

No — CVE-2026-43166 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
What is Out-of-bounds Write (CWE-787)?

The product writes data past the end or before the beginning of the intended buffer. View CWE-787 on MITRE CWE →