Linux: Use After Free
CVE-2026-52950 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 39fdac6be02eb7c3460518c1c4085f75f935c4ce, 827062952ed9bdf4220466c1f05ce452d04bdedf, 155a372a1cc50fa93387c5d3cdfd614a61e1afd1 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 0.18% 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 39fdac6be02eb7c3460518c1c4085f75f935c4ce or 827062952ed9bdf4220466c1f05ce452d04bdedf or 155a372a1cc50fa93387c5d3cdfd614a61e1afd1, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.18.33 or 7.0.10, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | eb289a5f6cc668853f9b2ea6aca04afe58ed11c7 up to, but not including, 39fdac6be02eb7c3460518c1c4085f75f935c4ce; eb289a5f6cc668853f9b2ea6aca04afe58ed11c7 up to, but not including, 827062952ed9bdf4220466c1f05ce452d04bdedf; eb289a5f6cc668853f9b2ea6aca04afe58ed11c7 up to, but not including, 155a372a1cc50fa93387c5d3cdfd614a61e1afd1; 6.18 | 39fdac6be02eb7c3460518c1c4085f75f935c4ce, 827062952ed9bdf4220466c1f05ce452d04bdedf, 155a372a1cc50fa93387c5d3cdfd614a61e1afd1 |
| Red Hat | Red Hat Enterprise Linux 10 | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 9 | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 6 | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 7 | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 8 | Not specified in the record | Not stated |
| Linux | Linux Kernel | 6.18 up to, but not including, 6.18.33; 6.19 up to, but not including, 7.0.10; 7.1 | 6.18.33, 7.0.10 |
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.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.8 | High | CNA |
| CVSS 3.1 | 7.0 | High | CNA |
Official description
In the Linux kernel, the following vulnerability has been resolved: drm/xe/dma-buf: fix UAF with retry loop Retry doesn't work here, since bo will be freed on error, leading to UAF. However, now that we do the alloc & init before the attach, we can now combine this as one unit and have the init do the alloc for us. This should make the retry safe. Reported by Sashiko. v2: Fix up the error unwind (CI) (cherry picked from commit 479669418253e0f27f8cf5db01a731352ea592e7)
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
Third-party and government advisories
- access.redhat.com/security/cve/CVE-2026-52950Third Party Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2492318Third Party Advisory
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52950.jsonThird Party Advisory
Recent Use After Free vulnerabilities
- 7.5 High severity
- 8.8 High severity
- 7.8 High severity
- 8.8 High severity
- 8.8 High severity
- 9.6 Critical severity
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