CVE-2026-64138

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.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/18d8db24b0a5b7be4829238dd4022236df02d421
https://git.kernel.org/stable/c/1c9d0646a9959752f11ca1080dc1ff26bd1756cb
https://git.kernel.org/stable/c/69f030cf95488ae1186c72ac8c66fd279664ea7f
https://git.kernel.org/stable/c/f0e5c9c663badc9982e6941322eef1cb17de0f11

Configurations

No configuration.

History

20 Jul 2026, 15:17

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 8.8

19 Jul 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-19 16:17

Updated : 2026-07-20 15:17

NVD link : CVE-2026-64138

Mitre link : CVE-2026-64138

CVE.ORG link : CVE-2026-64138

JSON object : View

Products Affected

No product.

CWE

No CWE.

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