SB2026052797 - NULL pointer dereference in Linux kernel bridge

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Main Vulnerability Database SB2026052797

SB2026052797 - NULL pointer dereference in Linux kernel bridge

Published: May 27, 2026

Security Bulletin ID SB2026052797
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Denial of service

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) NULL pointer dereference (CVE-ID: CVE-2026-46086)

CWE-ID: CWE-476 - NULL Pointer Dereference

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to a null pointer dereference in br_fdb_fillbuf() when reading bridge forwarding database entries through the brforward_read() sysfs path during a concurrent local FDB update. A local user can trigger concurrent access to cause a denial of service.

The issue arises because RCU readers can observe inconsistent values of f->dst across a check and a later dereference.


Remediation

Install update from vendor's website.

References