Linux: Use After Free
CVE-2026-64475 is a high-severity use after free vulnerability in Linux, with a CVSS 3.1 base score of 8.8 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 0f2a35a0c7ea7da347b814750eaa78adf3582381, 8d65decde9afd2bd78bcfffdc0df73b82a0b5509, ef4c38d30b3744e89eb5048218904bb629ea8d47 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 0.14% 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 0f2a35a0c7ea7da347b814750eaa78adf3582381 or 8d65decde9afd2bd78bcfffdc0df73b82a0b5509 or ef4c38d30b3744e89eb5048218904bb629ea8d47 or 9e0a3f642e607848669235f5069f35640abbfc88, whichever matches your release line, or a later version.
- Update Linux Kernel to 5.10.261 or 5.12 or 5.15.212 or 6.1.178, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 87856f9af04eaacf9848710625a4ffee1d020fa9 up to, but not including, 0f2a35a0c7ea7da347b814750eaa78adf3582381; 4aeec3984ddc853f7c65903bde472ffdef738bae up to, but not including, 8d65decde9afd2bd78bcfffdc0df73b82a0b5509; 4aeec3984ddc853f7c65903bde472ffdef738bae up to, but not including, ef4c38d30b3744e89eb5048218904bb629ea8d47; 4aeec3984ddc853f7c65903bde472ffdef738bae up to, but not including, 9e0a3f642e607848669235f5069f35640abbfc88; 4aeec3984ddc853f7c65903bde472ffdef738bae up to, but not including, 42d758a09d2c46c42357ecde9a5492f015bde2e5; 4aeec3984ddc853f7c65903bde472ffdef738bae up to, but not including, 52adb2dff7ce3d8430e2bdc5988b618a430def85; 4aeec3984ddc853f7c65903bde472ffdef738bae up to, but not including, 278a5659c391fe5afe5f9ce1bad1fd24e90144f1; 4aeec3984ddc853f7c65903bde472ffdef738bae up to, but not including, daedde7f024ecf88bc8e832ed40cf2c795f0796a; and 6 more ranges | 0f2a35a0c7ea7da347b814750eaa78adf3582381, 8d65decde9afd2bd78bcfffdc0df73b82a0b5509, ef4c38d30b3744e89eb5048218904bb629ea8d47, 9e0a3f642e607848669235f5069f35640abbfc88, 42d758a09d2c46c42357ecde9a5492f015bde2e5, 52adb2dff7ce3d8430e2bdc5988b618a430def85 |
| Linux | Linux Kernel | 5.10.37 up to, but not including, 5.10.261; 5.11.21 up to, but not including, 5.12; 5.12.4 up to, but not including, 5.15.212; 5.16 up to, but not including, 6.1.178; 6.2 up to, but not including, 6.6.145; 6.7 up to, but not including, 6.12.96; 6.13 up to, but not including, 6.18.39; 6.19 up to, but not including, 7.1.4; and 1 more ranges | 5.10.261, 5.12, 5.15.212, 6.1.178, 6.6.145, 6.12.96 |
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
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- 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:C/C:H/I:H/A:H. Scored by CNA.
Official description
In the Linux kernel, the following vulnerability has been resolved: vfio/pci: Release the VGA arbiter client on register_device() failure The re-order in the Fixes commit below displaced vfio_pci_vga_init() as the last failure point of what is now vfio_pci_core_register_device() without introducing an unwind for the VGA arbiter registration. In current kernels this is mostly benign because vfio_pci_set_decode() only uses pci_dev state, but the original failure path could leave a callback with a freed vdev cookie. The stale registration also becomes unsafe again once the callback follows drvdata to the vfio device. Add the required VGA unwind callout.
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/0f2a35a0c7ea7da347b814750eaa78adf3582381
- git.kernel.org/stable/c/278a5659c391fe5afe5f9ce1bad1fd24e90144f1
- git.kernel.org/stable/c/42d758a09d2c46c42357ecde9a5492f015bde2e5
- git.kernel.org/stable/c/52adb2dff7ce3d8430e2bdc5988b618a430def85
- git.kernel.org/stable/c/8d65decde9afd2bd78bcfffdc0df73b82a0b5509
- git.kernel.org/stable/c/9e0a3f642e607848669235f5069f35640abbfc88
- git.kernel.org/stable/c/daedde7f024ecf88bc8e832ed40cf2c795f0796a
- git.kernel.org/stable/c/ef4c38d30b3744e89eb5048218904bb629ea8d47
Recent Use After Free vulnerabilities
- 9.8 Critical 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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