SB20260815211 - Race condition in Linux kernel kcm



SB20260815211 - Race condition in Linux kernel kcm

Published: August 15, 2026

Security Bulletin ID SB20260815211
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) Race condition (CVE-ID: CVE-2026-74262)

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

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 cause a denial of service.

The vulnerability exists due to a race condition in kcm_attach() and kcm_unattach() callback handling in net/kcm/kcmsock.c when changing lower socket callbacks concurrently. A local user can trigger concurrent callback updates and execution to cause a denial of service.

The issue can lead to stale or misdirected wakeups when callback and sk_user_data state become mismatched across CPUs.


Remediation

Install update from vendor's website.