SB20260720406 - Race condition in Linux kernel bpf



SB20260720406 - Race condition in Linux kernel bpf

Published: July 20, 2026

Security Bulletin ID SB20260720406
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-2026-63865)

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

CVSSv4: 6.8 [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]


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

The vulnerability exists due to improper synchronization in sleepable bpf lsm hooks in kernel/bpf/bpf_lsm.c when executing the task_to_inode hook from rcu read-side critical sections. A local user can trigger the vulnerable hook to cause a denial of service.

The issue involves sleepable lsm programs being used with a hook that is invoked under rcu_read_lock().


Remediation

Install update from vendor's website.