Linux: Use After Free
CVE-2026-43138 is a high-severity use after free vulnerability in Linux, with a CVSS 3.1 base score of 7.8 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 09d6efc6abd42809956d598906c222ccd1c8ae92, 76801c3dfca0ac6339a23e9615b5f23e25b8644c, 1d7d869f074f98c34fe23f6a56e5f3acc1f95a2b 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 09d6efc6abd42809956d598906c222ccd1c8ae92 or 76801c3dfca0ac6339a23e9615b5f23e25b8644c or 1d7d869f074f98c34fe23f6a56e5f3acc1f95a2b or 16de4c6a8fe9ff497ca1aba33ef0dbee09f11952, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.12.75 or 6.18.16 or 6.19.6, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | cee544a40e4426040946e685988b1489f13e6600 up to, but not including, 09d6efc6abd42809956d598906c222ccd1c8ae92; cee544a40e4426040946e685988b1489f13e6600 up to, but not including, 76801c3dfca0ac6339a23e9615b5f23e25b8644c; cee544a40e4426040946e685988b1489f13e6600 up to, but not including, 1d7d869f074f98c34fe23f6a56e5f3acc1f95a2b; cee544a40e4426040946e685988b1489f13e6600 up to, but not including, 16de4c6a8fe9ff497ca1aba33ef0dbee09f11952; 6.9 | 09d6efc6abd42809956d598906c222ccd1c8ae92, 76801c3dfca0ac6339a23e9615b5f23e25b8644c, 1d7d869f074f98c34fe23f6a56e5f3acc1f95a2b, 16de4c6a8fe9ff497ca1aba33ef0dbee09f11952 |
| Linux | Linux Kernel | 6.9 up to, but not including, 6.12.75; 6.13 up to, but not including, 6.18.16; 6.19 up to, but not including, 6.19.6 | 6.12.75, 6.18.16, 6.19.6 |
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
- HighData or code can be modified at will.
- 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:H/A:H. Scored by NVD.
Official description
In the Linux kernel, the following vulnerability has been resolved: reset: gpio: suppress bind attributes in sysfs This is a special device that's created dynamically and is supposed to stay in memory forever. We also currently don't have a devlink between it and the actual reset consumer. Suppress sysfs bind attributes so that user-space can't unbind the device because - as of now - it will cause a use-after-free splat from any user that puts the reset control handle.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Use After Free
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.
How developers prevent this class of flaw
- Choose a language that provides automatic memory management.
- When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
Timeline
- CVE record published.
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Recent Use After Free vulnerabilities
- 8.8 High severity
- 8.8 High severity
- 8.3 High severity
- 8.8 High severity
- 8.8 High severity
- 8.3 High severity
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