---
id: CVE-2026-89758
title: >-
  kernel: mm/mempolicy: skip non-present PMDs when queueing folios
  (CVE-2026-89758)
summary: >-
  A flaw was found in the Linux kernel's memory management subsystem. When an
  HMM-based Graphics Processing Unit (GPU) driver migrates a Transparent Huge
  Page (THP) to device memory, it can leave a device-private Page Middle
  Directory (PMD) …
severity: high
cvss: 7
cvssVector: 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'
cvssSource: vendor
cwe: CWE-824
vendor: Red Hat
product: Red Hat Enterprise Linux 6
affected:
  - enterprise_linux 6
published: '2026-09-11'
updated: '2026-09-21'
sourceUpdated: '2026-09-21T17:54:36+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89758.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89758.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-89758'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532153'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-89758'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89758'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89758.mbox
  - url: 'https://git.kernel.org/stable/c/2858b4027f491e6fdb8ee2d8923798b619bf2791'
  - url: 'https://git.kernel.org/stable/c/3d927093b2add7ced588a926c3dc5d7a83f18596'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
  - score-dispute
epss: 0.00143
epssPercentile: 0.04004
scores:
  vendor: 4.7
  cna: 7.8
ingestedAt: '2026-09-14T15:23:07.472Z'
---

## Overview

A flaw was found in the Linux kernel's memory management subsystem. When an HMM-based Graphics Processing Unit (GPU) driver migrates a Transparent Huge Page (THP) to device memory, it can leave a device-private Page Middle Directory (PMD) entry. If a user-space application then attempts to manage this memory range, the kernel may incorrectly process the non-present PMD, leading to a system crash. This vulnerability could allow a local attacker to cause a Denial of Service (DoS).

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 6 · no fix planned: Red Hat Enterprise Linux 6 · updated 2026-09-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89758.json)

**kernel: mm/mempolicy: skip non-present PMDs when queueing folios** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-21.

Affected:

- Red Hat Enterprise Linux 6

No fix planned:

- Red Hat Enterprise Linux 6

Not affected:

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

## Remediation

Out of support scope