Linux: Use After Free
CVE-2026-64011 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 89ba026747019ee643d29407435ddc118e6ca908, fb29f6bbe433f3decad227588809636c25f2a287, 2dfdaaf7d933b676124aadec6698825e95f94fe9 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 89ba026747019ee643d29407435ddc118e6ca908 or fb29f6bbe433f3decad227588809636c25f2a287 or 2dfdaaf7d933b676124aadec6698825e95f94fe9 or e00f50f8697724a6f1d2d35744c1332c9912dac5, whichever matches your release line, or a later version.
- Update Linux Kernel to 5.10.259 or 5.15.210 or 6.1.176 or 6.6.143, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | b4011239a08e7e6c2c6e970dfa9e8ecb73139261 up to, but not including, 89ba026747019ee643d29407435ddc118e6ca908; b4011239a08e7e6c2c6e970dfa9e8ecb73139261 up to, but not including, fb29f6bbe433f3decad227588809636c25f2a287; b4011239a08e7e6c2c6e970dfa9e8ecb73139261 up to, but not including, 2dfdaaf7d933b676124aadec6698825e95f94fe9; b4011239a08e7e6c2c6e970dfa9e8ecb73139261 up to, but not including, e00f50f8697724a6f1d2d35744c1332c9912dac5; b4011239a08e7e6c2c6e970dfa9e8ecb73139261 up to, but not including, cdc17e09a636c7f936f771902535a7515a7608fc; b4011239a08e7e6c2c6e970dfa9e8ecb73139261 up to, but not including, 912ebc49d4406a17fe73e5671d674fbc2f6b2634; b4011239a08e7e6c2c6e970dfa9e8ecb73139261 up to, but not including, bc421d0826dedbba37580a25405eafb599e76d42; b4011239a08e7e6c2c6e970dfa9e8ecb73139261 up to, but not including, f4268b466190dae95a7585f69b4f1f8ad097632c; and 3 more ranges | 89ba026747019ee643d29407435ddc118e6ca908, fb29f6bbe433f3decad227588809636c25f2a287, 2dfdaaf7d933b676124aadec6698825e95f94fe9, e00f50f8697724a6f1d2d35744c1332c9912dac5, cdc17e09a636c7f936f771902535a7515a7608fc, 912ebc49d4406a17fe73e5671d674fbc2f6b2634 |
| Linux | Linux Kernel | 3.10.10 up to, but not including, 5.10.259; 5.11 up to, but not including, 5.15.210; 5.16 up to, but not including, 6.1.176; 6.2 up to, but not including, 6.6.143; 6.7 up to, but not including, 6.12.93; 6.13 up to, but not including, 6.18.35; 6.19 up to, but not including, 7.0.12; 7.1 | 5.10.259, 5.15.210, 6.1.176, 6.6.143, 6.12.93, 6.18.35 |
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: nfc: llcp: Fix use-after-free in llcp_sock_release() llcp_sock_release() unconditionally unlinks the socket from the local sockets list. However, if the socket is still in connecting state, it is on the connecting list. Fix this by checking the socket state and unlinking from the correct list.
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/2dfdaaf7d933b676124aadec6698825e95f94fe9
- git.kernel.org/stable/c/89ba026747019ee643d29407435ddc118e6ca908
- git.kernel.org/stable/c/912ebc49d4406a17fe73e5671d674fbc2f6b2634
- git.kernel.org/stable/c/bc421d0826dedbba37580a25405eafb599e76d42
- git.kernel.org/stable/c/cdc17e09a636c7f936f771902535a7515a7608fc
- git.kernel.org/stable/c/e00f50f8697724a6f1d2d35744c1332c9912dac5
- git.kernel.org/stable/c/f4268b466190dae95a7585f69b4f1f8ad097632c
- git.kernel.org/stable/c/fb29f6bbe433f3decad227588809636c25f2a287
Recent Use After Free vulnerabilities
- 8.8 High severity
- 9.8 Critical severity
- 9.8 Critical severity
- 7.8 High severity
- 9.8 Critical severity
- 8.8 High severity
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