SB2026072072 - Use-after-free in Linux kernel smb server

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Main Vulnerability Database SB2026072072

SB2026072072 - Use-after-free in Linux kernel smb server

Published: July 20, 2026

Security Bulletin ID SB2026072072
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Use-after-free (CVE-ID: CVE-2026-64142)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 6 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a remote user to cause a denial of service and potentially execute arbitrary code.

The vulnerability exists due to use-after-free in ksmbd durable handle management and m_fp_list walkers when processing concurrent durable-handle expiration and file lookup operations. A remote user can trigger concurrent durable handle expiration and lookup activity to cause a denial of service and potentially execute arbitrary code.

The issue involves a race between the durable scavenger and walkers such as ksmbd_lookup_fd_inode() and share-mode checks, and exploitation requires access to SMB operations that exercise durable handles.


Remediation

Install update from vendor's website.

References