Linux: Use After Free
CVE-2026-64051 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 9baafc2fea096279e75480f93fd5942e8336b510, 8dd6edbe26770df147136c3f2ac976c873b82650, 97a8e89cdef36207a8776edc03d6931763a06ad0 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 9baafc2fea096279e75480f93fd5942e8336b510 or 8dd6edbe26770df147136c3f2ac976c873b82650 or 97a8e89cdef36207a8776edc03d6931763a06ad0 or 8c795012d0e06b7740e40319b86ff8d2a435098d, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.6.142 or 6.12.92 or 6.18.34 or 7.0.11, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | ff13be8303336ead5621712f2c55012d738878b5 up to, but not including, 9baafc2fea096279e75480f93fd5942e8336b510; ff13be8303336ead5621712f2c55012d738878b5 up to, but not including, 8dd6edbe26770df147136c3f2ac976c873b82650; ff13be8303336ead5621712f2c55012d738878b5 up to, but not including, 97a8e89cdef36207a8776edc03d6931763a06ad0; ff13be8303336ead5621712f2c55012d738878b5 up to, but not including, 8c795012d0e06b7740e40319b86ff8d2a435098d; ff13be8303336ead5621712f2c55012d738878b5 up to, but not including, aa16b2bc0f02709919e2435f531406531e5bcc69; 6.4 | 9baafc2fea096279e75480f93fd5942e8336b510, 8dd6edbe26770df147136c3f2ac976c873b82650, 97a8e89cdef36207a8776edc03d6931763a06ad0, 8c795012d0e06b7740e40319b86ff8d2a435098d, aa16b2bc0f02709919e2435f531406531e5bcc69 |
| Linux | Linux Kernel | 6.4 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 | 6.6.142, 6.12.92, 6.18.34, 7.0.11 |
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: accel/qaic: Add overflow check to remap_pfn_range during mmap The call to remap_pfn_range in qaic_gem_object_mmap is susceptible to (re)mapping beyond the VMA if the BO is too large. This can cause use after free issues when munmap() unmaps only the VMA region and not the additional mappings. To prevent this, check the remaining size of the VMA before remapping and truncate the remapped length if sg->length is too large. [jhugo: fix braces from checkpatch --strict]
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/8c795012d0e06b7740e40319b86ff8d2a435098d
- git.kernel.org/stable/c/8dd6edbe26770df147136c3f2ac976c873b82650
- git.kernel.org/stable/c/97a8e89cdef36207a8776edc03d6931763a06ad0
- git.kernel.org/stable/c/9baafc2fea096279e75480f93fd5942e8336b510
- git.kernel.org/stable/c/aa16b2bc0f02709919e2435f531406531e5bcc69
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
Spotted an error? Tell us.