What is CVE-2026-64392?

CVE-2026-64392 is a Critical severity Linux kernel vulnerability with a CVSS score of 9.1 out of 10, affecting Linux kernel versions from 5.15 onward and patched in 6.6.145, 6.12.96, 6.18.39 and others. CVE-2026-64392 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-64392?

CVE-2026-64392 has a CVSS score of 9.1 out of 10, rated Critical severity. The vector string is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H.

Is there a patch available for CVE-2026-64392?

Yes, CVE-2026-64392 has been patched. Fixed versions include 6.6.145, 6.12.96, 6.18.39 and others. If you are running Linux kernel 5.15 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-64392 actively exploited?

CVE-2026-64392 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-64392

Critical

In the Linux kernel, the following vulnerability has been resolved: ksmbd: use opener credentials for delete-on-close Delete-on-close can be completed by deferred or durable handle teardown, where no request work is available. Both the base-file unlink and the ADS xattr removal consequently run with the ksmbd worker credentials and can bypass filesystem permission checks. Run both operations with the credentials captured in struct file when the handle was opened. This preserves the authenticated user's fsuid, fsgid, supplementary groups and capability restrictions at final close.

Package Linux Kernel

Published 2026-07-25

Last modified 2026-09-04

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

9.1

out of 10

Critical

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

High

Availability

High

Vector string

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

Affected versions

Linux kernel versions 5.15 and later are affected. Fixed in 6.6.145, 6.12.96, 6.18.39, 7.1.4, 7.2 and their respective stable series.

Affected from

≥ 5.15

Fixed in

✓ 6.6.145 6.6.x ✓ 6.12.96 6.12.x ✓ 6.18.39 6.18.x ✓ 7.1.4 7.1.x ✓ 7.2

References

5 total

Kernel Git
https://git.kernel.org/stable/c/18c59109bb6fb816d5102171666f87cf1e29901d

Patch
Kernel Git
https://git.kernel.org/stable/c/4b7059974549d278e30fe70e2a4e421f9839817d

Patch
Kernel Git
https://git.kernel.org/stable/c/52e2f21911158ec961cd5aae19c56460db382af0

Patch
Kernel Git
https://git.kernel.org/stable/c/e72c15085b6d86f45d224d98aa75b5cace4aaab9

Patch
Kernel Git
https://git.kernel.org/stable/c/f08b3f451f12eee4abd8a5981803bc36db84458b

Patch

Details

CVE ID CVE-2026-64392

Severity Critical

CVSS score 9.1 / 10

CVSS version 3.1

Published 2026-07-25

Modified 2026-09-04

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-64392?

CVE-2026-64392 is a Critical severity Linux kernel vulnerability with a CVSS score of 9.1 out of 10 . It affects Linux kernel versions from 5.15 onward and has been patched in 6.6.145, 6.12.96, 6.18.39 and others. CVE-2026-64392 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-64392?

CVE-2026-64392 has a CVSS score of 9.1 out of 10, rated Critical severity (CVSS 3.1). The vector string is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H.
Is there a patch available for CVE-2026-64392?

Yes. CVE-2026-64392 has been patched. Fixed versions include 6.6.145, 6.12.96, 6.18.39 and others. If you are running Linux kernel 5.15 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-64392 actively exploited?

No. CVE-2026-64392 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.