CVE-2026-64257

In the Linux kernel, the following vulnerability has been resolved: smb: client: reject overlapping data areas in SMB2 responses Commit 53b7c271f06b ("smb: client: restrict implied bcc[0] exemption to responses without data area") restricted the implied bcc[0] length exception to responses without a data area. However, the overlap handling in __smb2_calc_size() clears data_length, which can make an invalid response appear to have no data area and so qualify for the exception. Track data area overlap separately and reject such responses before applying the length compatibility exceptions.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/36bfa52459e45c0d5b668de2f1c91f6dc5c67775	Patch
https://git.kernel.org/stable/c/445ece263131780dee273d727a4d6f11934feec7	Patch
https://git.kernel.org/stable/c/4a9d2657d3e05f6ed09c148cb127b4e58702275f	Patch
https://git.kernel.org/stable/c/57cba95f0e97c6f6e45e6731da30aff091bd7460	Patch
https://git.kernel.org/stable/c/8986c932905ea508d66da421eb2eb6e676ace1fe	Patch
https://git.kernel.org/stable/c/fdafa1e68dc75045b7b617e6e7d2854950804d83	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:7.2:rc3::::::

History

No history.

Information

Published : 2026-07-25 10:17

Updated : 2026-08-17 05:17

NVD link : CVE-2026-64257

Mitre link : CVE-2026-64257

CVE.ORG link : CVE-2026-64257

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo

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