CVE-2026-64388

In the Linux kernel, the following vulnerability has been resolved: smb/client: fix chown/chgrp with SMB3 POSIX Extensions Ownership (chown) and group (chgrp) modifications were being ignored when mounting with SMB3 POSIX Extensions unless CIFS_MOUNT_CIFS_ACL or CIFS_MOUNT_MODE_FROM_SID were also explicitly set. Fix this by checking for posix_extensions in cifs_setattr_nounix() when updating UID and GID, ensuring that id_mode_to_cifs_acl() is called to map and set the ownership/group information on the server.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

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/27ead8c5418af6bfab711079fecb9414d78d4cae
https://git.kernel.org/stable/c/3eaec47518e126e6dcd1a48521d740278073f0ec
https://git.kernel.org/stable/c/550cfb8a81181331d4d0f76ab75ee58a0bf41e3e	Patch
https://git.kernel.org/stable/c/6825a45f6b8ef76b0ee32649ec3d6e39ca143a18
https://git.kernel.org/stable/c/760ef2c579c2609cf17fb1cd5392f64d42d43d33	Patch
https://git.kernel.org/stable/c/c0fe1118a1471d459f76c3e70ff2abbf784ce6bf

Configurations

Configuration 1 (hide)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

History

30 Oct 2026, 13:19

Type	Values Removed	Values Added
References		() https://git.kernel.org/stable/c/c0fe1118a1471d459f76c3e70ff2abbf784ce6bf -

21 Oct 2026, 13:19

Type	Values Removed	Values Added
References		() https://git.kernel.org/stable/c/27ead8c5418af6bfab711079fecb9414d78d4cae - () https://git.kernel.org/stable/c/6825a45f6b8ef76b0ee32649ec3d6e39ca143a18 -

19 Oct 2026, 21:17

Type	Values Removed	Values Added
CWE		CWE-682

15 Oct 2026, 11:17

Type	Values Removed	Values Added
References		() https://git.kernel.org/stable/c/3eaec47518e126e6dcd1a48521d740278073f0ec -

Information

Published : 2026-07-25 10:17

Updated : 2026-10-30 13:19

NVD link : CVE-2026-64388

Mitre link : CVE-2026-64388

CVE.ORG link : CVE-2026-64388

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo CWE-682

Incorrect Calculation

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