---
id: CVE-2026-89518
title: >-
  kernel: sched_ext: Fix this_rq() assumptions in dispatch kfuncs
  (CVE-2026-89518)
summary: >-
  A flaw was found in the Linux kernel's `sched_ext` component. Under core
  scheduling, incorrect assumptions in dispatch kfuncs regarding `this_rq()` can
  lead to a deadlock. This occurs when an `rq` lock is acquired on a CPU
  different from t…
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cvssSource: vendor
cwe: CWE-833
vendor: Red Hat
product: Linux
affected:
  - >-
    Linux >= 4c95380701f58b8112f0b891de8d160e4199e19d <
    6d1890d3c6137ab523799765ae2de62cc05f116d
  - >-
    Linux >= 4c95380701f58b8112f0b891de8d160e4199e19d <
    3dd52416e44a70bc993adb96d2e0d71b9ea21359
  - Linux 6.19
published: '2026-09-11'
updated: '2026-09-14'
sourceUpdated: '2026-09-14T08:39:29+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89518.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89518.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-89518'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532018'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-89518'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89518'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89518.mbox
  - url: 'https://git.kernel.org/stable/c/6d1890d3c6137ab523799765ae2de62cc05f116d'
  - url: 'https://git.kernel.org/stable/c/3dd52416e44a70bc993adb96d2e0d71b9ea21359'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
epss: 0.00198
epssPercentile: 0.08523
ingestedAt: '2026-09-14T11:11:19.887Z'
---

## Overview

A flaw was found in the Linux kernel's `sched_ext` component. Under core scheduling, incorrect assumptions in dispatch kfuncs regarding `this_rq()` can lead to a deadlock. This occurs when an `rq` lock is acquired on a CPU different from the dispatched `rq`'s, potentially causing the system to become unresponsive. This vulnerability could result in a Denial of Service (DoS).

## Vendor advisories

- **Red Hat VEX** · Moderate · updated 2026-09-14 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89518.json)

**kernel: sched_ext: Fix this_rq() assumptions in dispatch kfuncs** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-14.

Not affected:

- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4

## Remediation

Refer to the advisory for fix availability.