CVE-2026-64257

Updated on 25 Jul 2026

Severity

9.1 Critical severity

Details

CVSS score
9.1
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Overview

About vulnerability

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.

Details

Affected product:
CentOS 8.5 ELS , TuxCare 9.6 ESU
Affected packages:
kernel @ 5.14.0 (+1 more)

Fixes

KernelCare state

Live-patch status from KernelCare for each operating system.

Operating system Status Covered kernels
AlmaLinux 9.6 ESU Planned —