Linux: Use After Free
CVE-2026-64221 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 9c6f306a8140962c7284197db54b96fdb5f468d6, 3bbbe7ae3fdada0df4157c1ffe989f92dfa8dcd6, d6f422b122922d1abee907d673bcc990e5f3672d 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 9c6f306a8140962c7284197db54b96fdb5f468d6 or 3bbbe7ae3fdada0df4157c1ffe989f92dfa8dcd6 or d6f422b122922d1abee907d673bcc990e5f3672d or f2dc841d7dc9063fe9b47ced869b1271e55052ae, whichever matches your release line, or a later version.
- Update Linux Kernel to 5.10.258 or 5.15.209 or 6.1.175 or 6.6.142, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | c687c46e9e4527c4b4d82bc3cca58c1b08bcfb83 up to, but not including, 9c6f306a8140962c7284197db54b96fdb5f468d6; c687c46e9e4527c4b4d82bc3cca58c1b08bcfb83 up to, but not including, 3bbbe7ae3fdada0df4157c1ffe989f92dfa8dcd6; c687c46e9e4527c4b4d82bc3cca58c1b08bcfb83 up to, but not including, d6f422b122922d1abee907d673bcc990e5f3672d; c687c46e9e4527c4b4d82bc3cca58c1b08bcfb83 up to, but not including, f2dc841d7dc9063fe9b47ced869b1271e55052ae; c687c46e9e4527c4b4d82bc3cca58c1b08bcfb83 up to, but not including, 1cd927002120678bd5d23c760246639caa53040e; c687c46e9e4527c4b4d82bc3cca58c1b08bcfb83 up to, but not including, d7a076fb596c7b408ed6df74793a597990a6d860; c687c46e9e4527c4b4d82bc3cca58c1b08bcfb83 up to, but not including, 178b9b570c0f75fa7e691490520328b20d19138e; c687c46e9e4527c4b4d82bc3cca58c1b08bcfb83 up to, but not including, ea6ec3343e05f7937a53eb6d7617b3abdb4abc19; and 1 more ranges | 9c6f306a8140962c7284197db54b96fdb5f468d6, 3bbbe7ae3fdada0df4157c1ffe989f92dfa8dcd6, d6f422b122922d1abee907d673bcc990e5f3672d, f2dc841d7dc9063fe9b47ced869b1271e55052ae, 1cd927002120678bd5d23c760246639caa53040e, d7a076fb596c7b408ed6df74793a597990a6d860 |
| Linux | Linux Kernel | 4.12 up to, but not including, 5.10.258; 5.11 up to, but not including, 5.15.209; 5.16 up to, but not including, 6.1.175; 6.2 up to, but not including, 6.6.142; 6.7 up to, but not including, 6.12.92; 6.13 up to, but not including, 6.18.34; 6.19 up to, but not including, 7.0.11; 7.1 | 5.10.258, 5.15.209, 6.1.175, 6.6.142, 6.12.92, 6.18.34 |
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: spi: ti-qspi: fix use-after-free after DMA setup failure The driver falls back to PIO mode if DMA setup fails during probe. Make sure to clear the DMA channel pointer also if buffer allocation fails to avoid passing a pointer to the released channel to the DMA engine (or trying to free the channel a second time on late probe errors or driver unbind). This issue was flagged by Sashiko when reviewing a devres allocation conversion patch.
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/178b9b570c0f75fa7e691490520328b20d19138e
- git.kernel.org/stable/c/1cd927002120678bd5d23c760246639caa53040e
- git.kernel.org/stable/c/3bbbe7ae3fdada0df4157c1ffe989f92dfa8dcd6
- git.kernel.org/stable/c/9c6f306a8140962c7284197db54b96fdb5f468d6
- git.kernel.org/stable/c/d6f422b122922d1abee907d673bcc990e5f3672d
- git.kernel.org/stable/c/d7a076fb596c7b408ed6df74793a597990a6d860
- git.kernel.org/stable/c/ea6ec3343e05f7937a53eb6d7617b3abdb4abc19
- git.kernel.org/stable/c/f2dc841d7dc9063fe9b47ced869b1271e55052ae
Recent Use After Free vulnerabilities
- 7.8 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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