CVE-2026-64391

In the Linux kernel, the following vulnerability has been resolved: ksmbd: use opener credentials for ADS I/O Alternate data streams are stored as xattrs. Unlike regular file I/O, their read and write paths therefore call VFS xattr helpers which recheck inode permissions and LSM policy using the current task credentials. Run ADS I/O with the credentials captured when the SMB handle was opened.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/222c4c52c3af2d0f68de31182710df3508a31095
https://git.kernel.org/stable/c/2ad5509dd576ae16d252d4698daf03002f9e0234
https://git.kernel.org/stable/c/2b4592cea214683de0f2ce6f8c22c097fb0ea1ab	Patch
https://git.kernel.org/stable/c/52a56cf53ec834c44ac1b4d16d585f26613ee5ce	Patch
https://git.kernel.org/stable/c/a8f5d39971bbad9340d49cd41b0e2da9452a649d	Patch
https://git.kernel.org/stable/c/baa5e094886fffa7e6272edcb5e08be5ce28262c	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	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/222c4c52c3af2d0f68de31182710df3508a31095 -

21 Oct 2026, 13:19

Type	Values Removed	Values Added
References		() https://git.kernel.org/stable/c/2ad5509dd576ae16d252d4698daf03002f9e0234 -

Information

Published : 2026-07-25 10:17

Updated : 2026-10-30 13:19

NVD link : CVE-2026-64391

Mitre link : CVE-2026-64391

CVE.ORG link : CVE-2026-64391

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo

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