---
id: CVE-2026-89759
title: >-
  kernel: mm/kmemleak: avoid soft lockup when scanning task stacks
  (CVE-2026-89759)
summary: >-
  A flaw was found in the Linux kernel's memory leak detector (kmemleak). When
  kmemleak_scan() attempts to scan task stacks on systems with a large number of
  threads, it can hold a CPU for an extended period without allowing other
  processes …
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-1050
vendor: Red Hat
product: Red Hat Enterprise Linux 9
affected:
  - enterprise_linux 10
  - enterprise_linux 6
  - enterprise_linux 8
  - enterprise_linux 9
  - openshift_container_platform 4
published: '2026-09-11'
updated: '2026-09-15'
sourceUpdated: '2026-09-15T11:49:06+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89759.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89759.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-89759'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532495'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-89759'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89759'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89759.mbox
  - url: 'https://git.kernel.org/stable/c/9a1b12c06c192290b8479de48f66f1e75d89c4b7'
  - url: 'https://git.kernel.org/stable/c/3fc8044251de21555fb02c365fa681bab8b0db55'
  - url: 'https://git.kernel.org/stable/c/1838c704bcb4fd3556cf67513c6f97a39099e35c'
  - url: 'https://git.kernel.org/stable/c/5d10d4e19e6daa487f0cd0ea6cba472325de92f9'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
epss: 0.00209
epssPercentile: 0.09809
ingestedAt: '2026-09-14T11:11:19.884Z'
---

## Overview

A flaw was found in the Linux kernel's memory leak detector (kmemleak). When kmemleak_scan() attempts to scan task stacks on systems with a large number of threads, it can hold a CPU for an extended period without allowing other processes to run. This can lead to a 'soft lockup,' where the system becomes unresponsive, effectively causing a Denial of Service (DoS).

## Vendor advisories

- **Red Hat VEX** · Low · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, … · updated 2026-09-15 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89759.json)

**kernel: mm/kmemleak: avoid soft lockup when scanning task stacks** — rated Low by Red Hat. Released 2026-09-11, updated 2026-09-15.

Affected:

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

No fix planned:

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

Not affected:

- Red Hat Enterprise Linux 7

## Remediation

Out of support scope