SB2026040153 - Race condition in Linux kernel apparmor



SB2026040153 - Race condition in Linux kernel apparmor

Published: April 1, 2026

Security Bulletin ID SB2026040153
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 security vulnerability.


1) Race condition (CVE-ID: CVE-2026-23411)

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

The vulnerability exists due to a race condition in the AppArmor i_private data management when accessing filesystem callback functions after reference removal. A local attacker can trigger a use-after-free condition by exploiting the race between freeing data and filesystem access to trigger a denial of service.

The issue arises when the inode persists beyond AppArmor data cleanup and filesystem callbacks are invoked after the reference has been released. This race condition primarily affects data stored in i_private, including rawdata/loaddata interfaces.


Remediation

Install update from vendor's website.