SB20261022113 - NULL pointer dereference in Linux kernel kernel/workqueue.c: check_flush_dependency()



SB20261022113 - NULL pointer dereference in Linux kernel kernel/workqueue.c: check_flush_dependency()

Published: October 22, 2026

Security Bulletin ID SB20261022113
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-2026-98537)

CWE-ID: CWE-476 - NULL Pointer Dereference

CVSSv4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a local user to potentially cause a denial of service by triggering a kernel NULL pointer dereference.

The vulnerability exists due to a NULL pointer dereference in the Linux kernel workqueue function check_flush_dependency() when checking flush dependencies for a worker that is not executing a work item. A local user can potentially trigger this condition during worker creation when memory allocation invokes an out-of-memory notifier, causing the function to dereference worker->current_pwq while it is NULL and potentially cause a denial of service.


Remediation

Install update from vendor's website.