CVE-2026-43042

HIGHCVSS 7.1/10EPSS 0.11%

Last modified

CVE-2026-43042 is a high-severity vulnerability rated 7.1/10 on the CVSS scale. 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. EPSS estimates a 0.11% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1
7.1/10

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

EPSS Probability
0.11%

1.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

VendorProductVersionsUpdate
LinuxLinux Kernel>= 4.1, < 6.19.12
LinuxLinux Kernel7.0Rc1

References

Timeline

Published
Last Modified
Status
Analyzed

Frequently Asked Questions

What is CVE-2026-43042?
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.
How severe is CVE-2026-43042?
CVE-2026-43042 has a CVSS score of 7.1/10 (HIGH severity). The EPSS model estimates a 0.11% probability of exploitation in the next 30 days.
How do I fix CVE-2026-43042?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-43042?

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Source: NVD / NIST