Linux: Out-of-bounds Read
CVE-2026-43042 is a high-severity out-of-bounds read vulnerability in Linux, with a CVSS 3.1 base score of 7.1 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 6b9184ebc936f791631e51e783ab30320b3770e4, 0d377825548fe598595b5a5fa4a309fb593d8fb4, 8adc5b6fc876928d8c95555d30b66fa50b07421e as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.13% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Linux to 6b9184ebc936f791631e51e783ab30320b3770e4 or 0d377825548fe598595b5a5fa4a309fb593d8fb4 or 8adc5b6fc876928d8c95555d30b66fa50b07421e or 5bb3caf0bbfb56f1a00d2af072ac3d8395a3b9ef, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.19.12 or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 7720c01f3f590116882e251f13c7e1d5602f8643 up to, but not including, 6b9184ebc936f791631e51e783ab30320b3770e4; 7720c01f3f590116882e251f13c7e1d5602f8643 up to, but not including, 0d377825548fe598595b5a5fa4a309fb593d8fb4; 7720c01f3f590116882e251f13c7e1d5602f8643 up to, but not including, 8adc5b6fc876928d8c95555d30b66fa50b07421e; 7720c01f3f590116882e251f13c7e1d5602f8643 up to, but not including, 5bb3caf0bbfb56f1a00d2af072ac3d8395a3b9ef; 7720c01f3f590116882e251f13c7e1d5602f8643 up to, but not including, 629ec78ef8608d955ce217880cdc3e1873af3a15; 4.1 | 6b9184ebc936f791631e51e783ab30320b3770e4, 0d377825548fe598595b5a5fa4a309fb593d8fb4, 8adc5b6fc876928d8c95555d30b66fa50b07421e, 5bb3caf0bbfb56f1a00d2af072ac3d8395a3b9ef, 629ec78ef8608d955ce217880cdc3e1873af3a15 |
| Linux | Linux Kernel | 4.1 up to, but not including, 6.19.12; 7.0 | 6.19.12 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H. Scored by CNA.
Official 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.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Out-of-bounds Read
The product reads data past the end, or before the beginning, of the intended buffer.
How developers prevent this class of flaw
- Use a language that provides appropriate memory abstractions.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other references
Recent Out-of-bounds Read vulnerabilities
- 8.1 High severity
- 8.8 High severity
- 7.3 High severity
- 7.1 High severity
- 7.1 High severity
- 7.1 High severity
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