What is CVE-2026-43042?

CVE-2026-43042 is a High severity Linux kernel vulnerability with a CVSS score of 7.1 out of 10, classified as a Out-of-bounds Read flaw (CWE-125), affecting Linux kernel versions from 4.1 onward and patched in 6.19.12 and 7.0. CVE-2026-43042 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-43042?

CVE-2026-43042 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:L/UI:N/S:U/C:H/I:N/A:H.

Is there a patch available for CVE-2026-43042?

Yes, CVE-2026-43042 has been patched. Fixed versions include 6.19.12 and 7.0. If you are running Linux kernel 4.1 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-43042 actively exploited?

CVE-2026-43042 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is Out-of-bounds Read (CWE-125)?

The product reads data past the end or before the beginning of the intended buffer. See MITRE CWE for full details: https://cwe.mitre.org/data/definitions/125.html

CVE-2026-43042

High

In the Linux kernel, the following vulnerability has been resolved: mpls: add seqcount to protect the platform_label{,s} pair The RCU-protected codepaths (mpls_forward, mpls_dump_routes) can have an inconsistent view of platform_labels vs platform_label in case of a concurrent resize (resize_platform_label_table, under platform_mutex). This can lead to OOB accesses. This patch adds a seqcount, so that we get a consistent snapshot. Note that mpls_label_ok is also susceptible to this, so the check against RTA_DST in rtm_to_route_config, done outside platform_mutex, is not sufficient. This value gets passed to mpls_label_ok once more in both mpls_route_add and mpls_route_del, so there is no issue, but that additional check must not be removed.

Package Linux Kernel

Published 2026-05-01

Last modified 2026-05-08

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

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

High

Vector string

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

Weakness type

CWE-125

CVE-2026-43042 is a Out-of-bounds Read vulnerability

What is Out-of-bounds Read?

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

Affected versions

Linux kernel versions 4.1 and later are affected. Fixed in 6.19.12, 7.0 and their respective stable series.

Affected from

≥ 4.1

Fixed in

✓ 6.19.12 6.19.x ✓ 7.0

References

The following references provide additional information about CVE-2026-43042 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/5bb3caf0bbfb56f1a00d2af072ac3d8395a3b9ef
Patch
Kernel patch commit
https://git.kernel.org/stable/c/629ec78ef8608d955ce217880cdc3e1873af3a15
Patch

Details

CVE ID CVE-2026-43042

Severity High

CVSS score 7.1 / 10

CVSS version 3.1

Published 2026-05-01

Modified 2026-05-08

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-43042?

CVE-2026-43042 is a High severity Linux kernel vulnerability with a CVSS score of 7.1 out of 10 , classified as an Out-of-bounds Read flaw (CWE-125) . It affects Linux kernel versions from 4.1 onward and has been patched in 6.19.12 and 7.0. CVE-2026-43042 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-43042?

CVE-2026-43042 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:L/UI:N/S:U/C:H/I:N/A:H.
Is there a patch available for CVE-2026-43042?

Yes — CVE-2026-43042 has been patched. Fixed versions include 6.19.12 and 7.0. If you are running Linux kernel 4.1 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-43042 actively exploited?

No — CVE-2026-43042 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
What is Out-of-bounds Read (CWE-125)?

The product reads data past the end or before the beginning of the intended buffer. View CWE-125 on MITRE CWE →