Linux: Use After Free
CVE-2026-43426 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 c7012fc73dab4829404fedeeaa8531f12ac8545f, 51afaf919bbaacdd9cc9e146033ae0a743a42dd7, 1899edac312ef17a7234851686e8a703f56d0a84 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 c7012fc73dab4829404fedeeaa8531f12ac8545f or 51afaf919bbaacdd9cc9e146033ae0a743a42dd7 or 1899edac312ef17a7234851686e8a703f56d0a84 or 9c6159d5b72d5fc265cce5da04f27d730b552e69, whichever matches your release line, or a later version.
- Update Linux Kernel to 5.10.253 or 5.15.203 or 6.1.167 or 6.6.130, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | f1407d5c66240b33d11a7f1a41d55ccf6a9d7647 up to, but not including, c7012fc73dab4829404fedeeaa8531f12ac8545f; f1407d5c66240b33d11a7f1a41d55ccf6a9d7647 up to, but not including, 51afaf919bbaacdd9cc9e146033ae0a743a42dd7; f1407d5c66240b33d11a7f1a41d55ccf6a9d7647 up to, but not including, 1899edac312ef17a7234851686e8a703f56d0a84; f1407d5c66240b33d11a7f1a41d55ccf6a9d7647 up to, but not including, 9c6159d5b72d5fc265cce5da04f27d730b552e69; f1407d5c66240b33d11a7f1a41d55ccf6a9d7647 up to, but not including, 6287e0c01ccb818e7214f88d885ffb7c9e81b0e0; f1407d5c66240b33d11a7f1a41d55ccf6a9d7647 up to, but not including, 0b7d11fd6e742ecc0b1eca44b4f0b93140c74bae; f1407d5c66240b33d11a7f1a41d55ccf6a9d7647 up to, but not including, 6ffe44f022c95b1b29c691d2169c5abc046f7580; f1407d5c66240b33d11a7f1a41d55ccf6a9d7647 up to, but not including, 3cbc242b88c607f55da3d0d0d336b49bf1e20412; and 1 more ranges | c7012fc73dab4829404fedeeaa8531f12ac8545f, 51afaf919bbaacdd9cc9e146033ae0a743a42dd7, 1899edac312ef17a7234851686e8a703f56d0a84, 9c6159d5b72d5fc265cce5da04f27d730b552e69, 6287e0c01ccb818e7214f88d885ffb7c9e81b0e0, 0b7d11fd6e742ecc0b1eca44b4f0b93140c74bae |
| Linux | Linux Kernel | 3.0 up to, but not including, 5.10.253; 5.11 up to, but not including, 5.15.203; 5.16 up to, but not including, 6.1.167; 6.2 up to, but not including, 6.6.130; 6.7 up to, but not including, 6.12.78; 6.13 up to, but not including, 6.18.19; 6.19 up to, but not including, 6.19.9; 7.0 | 5.10.253, 5.15.203, 6.1.167, 6.6.130, 6.12.78, 6.18.19 |
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: usb: renesas_usbhs: fix use-after-free in ISR during device removal In usbhs_remove(), the driver frees resources (including the pipe array) while the interrupt handler (usbhs_interrupt) is still registered. If an interrupt fires after usbhs_pipe_remove() but before the driver is fully unbound, the ISR may access freed memory, causing a use-after-free. Fix this by calling devm_free_irq() before freeing resources. This ensures the interrupt handler is both disabled and synchronized (waits for any running ISR to complete) before usbhs_pipe_remove() is called.
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
- git.kernel.org/stable/c/0b7d11fd6e742ecc0b1eca44b4f0b93140c74bae
- git.kernel.org/stable/c/1899edac312ef17a7234851686e8a703f56d0a84
- git.kernel.org/stable/c/3cbc242b88c607f55da3d0d0d336b49bf1e20412
- git.kernel.org/stable/c/51afaf919bbaacdd9cc9e146033ae0a743a42dd7
- git.kernel.org/stable/c/6287e0c01ccb818e7214f88d885ffb7c9e81b0e0
- git.kernel.org/stable/c/6ffe44f022c95b1b29c691d2169c5abc046f7580
- git.kernel.org/stable/c/9c6159d5b72d5fc265cce5da04f27d730b552e69
- git.kernel.org/stable/c/c7012fc73dab4829404fedeeaa8531f12ac8545f
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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