Linux: Use After Free
CVE-2026-43332 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 9e796001af97a1f7368d5114b7a8533dd98d797a, 604da9c04c218362e1c1457304ebeb9c199d537c, c4c7219e93319bba9ba0765dee597784c78f63c5 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 0.16% 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 9e796001af97a1f7368d5114b7a8533dd98d797a or 604da9c04c218362e1c1457304ebeb9c199d537c or c4c7219e93319bba9ba0765dee597784c78f63c5 or 4d390f0e507dfb16d58f83a58d78d1150dc8b9d7, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.6.134 or 6.12.81 or 6.18.22 or 6.19.12, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 335176dd8ebaca6493807dceea33c478305667fa up to, but not including, 9e796001af97a1f7368d5114b7a8533dd98d797a; 04e6ccfc93c5a1aa1d75a537cf27e418895e20ea up to, but not including, 604da9c04c218362e1c1457304ebeb9c199d537c; 04e6ccfc93c5a1aa1d75a537cf27e418895e20ea up to, but not including, c4c7219e93319bba9ba0765dee597784c78f63c5; 04e6ccfc93c5a1aa1d75a537cf27e418895e20ea up to, but not including, 4d390f0e507dfb16d58f83a58d78d1150dc8b9d7; 04e6ccfc93c5a1aa1d75a537cf27e418895e20ea up to, but not including, 9e07e3b81807edd356e1f794cffa00a428eff443; 02871710b93058eb1249d5847c0b2d1c2c3c98ae; 6.6.14 up to, but not including, 6.6.134; 6.7.2 up to, but not including, 6.8; and 1 more ranges | 9e796001af97a1f7368d5114b7a8533dd98d797a, 604da9c04c218362e1c1457304ebeb9c199d537c, c4c7219e93319bba9ba0765dee597784c78f63c5, 4d390f0e507dfb16d58f83a58d78d1150dc8b9d7, 9e07e3b81807edd356e1f794cffa00a428eff443, 6.6.134 |
| Linux | Linux Kernel | 6.6.14 up to, but not including, 6.6.134; 6.8 up to, but not including, 6.12.81; 6.13 up to, but not including, 6.18.22; 6.19 up to, but not including, 6.19.12; 6.7.2; 7.0 | 6.6.134, 6.12.81, 6.18.22, 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
- 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 CNA.
Official description
In the Linux kernel, the following vulnerability has been resolved: thermal: core: Fix thermal zone device registration error path If thermal_zone_device_register_with_trips() fails after registering a thermal zone device, it needs to wait for the tz->removal completion like thermal_zone_device_unregister(), in case user space has managed to take a reference to the thermal zone device's kobject, in which case thermal_release() may not be called by the error path itself and tz may be freed prematurely. Add the missing wait_for_completion() call to the thermal zone device registration error path.
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.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- git.kernel.org/stable/c/4d390f0e507dfb16d58f83a58d78d1150dc8b9d7
- git.kernel.org/stable/c/604da9c04c218362e1c1457304ebeb9c199d537c
- git.kernel.org/stable/c/9e07e3b81807edd356e1f794cffa00a428eff443
- git.kernel.org/stable/c/9e796001af97a1f7368d5114b7a8533dd98d797a
- git.kernel.org/stable/c/c4c7219e93319bba9ba0765dee597784c78f63c5
Recent Use After Free vulnerabilities
- 7.3 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
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