CVE-2026-64138

High

In the Linux kernel, the following vulnerability has been resolved: ksmbd: validate SID in parent security descriptor during ACL inheritance Introduce smb_validate_ntsd_sid() helper to safely validate Owner SID and Group SID inside the NT Security Descriptor (smb_ntsd) retrieved from the parent directory.

Package Linux Kernel
Published 2026-07-19
Last modified 2026-08-18
CVSS version 3.1
Patch available
Yes

CVSS 3.1 score

8.8

out of 10
High
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Vector string
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected versions

Linux kernel versions 5.15 and later are affected. Fixed in 6.12.92, 6.18.34, 7.0.11, 7.1 and their respective stable series.

Affected from
≥ 5.15
Fixed in
✓ 6.12.92 6.12.x ✓ 6.18.34 6.18.x ✓ 7.0.11 7.0.x ✓ 7.1

References

4 total

Frequently asked questions

  • What is CVE-2026-64138?

    CVE-2026-64138 is a High severity Linux kernel vulnerability with a CVSS score of 8.8 out of 10 . It affects Linux kernel versions from 5.15 onward and has been patched in 6.12.92, 6.18.34, 7.0.11 and others. CVE-2026-64138 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • What is the CVSS score for CVE-2026-64138?

    CVE-2026-64138 has a CVSS score of 8.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H .

  • Is there a patch available for CVE-2026-64138?

    Yes. CVE-2026-64138 has been patched. Fixed versions include 6.12.92, 6.18.34, 7.0.11 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-2026-64138 actively exploited?

    No. CVE-2026-64138 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

Back to
All CVEs
View on
NVD / NIST