---
id: CVE-2025-38733
title: >-
  kernel: Linux kernel: Denial of Service due to incorrect lowcore memory
  mapping (CVE-2025-38733)
summary: >-
  A flaw was found in the Linux kernel. Due to an incorrect identity mapping of
  the lowcore, a critical memory region, NULL pointer accesses may succeed
  instead of causing an exception. This vulnerability allows a local attacker to
  cause a D…
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-476
vendor: Red Hat
product: Red Hat Enterprise Linux 9
affected:
  - enterprise_linux 10
  - enterprise_linux 9
published: '2025-09-05'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T23:23:59+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-38733.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-38733.json
  - url: 'https://access.redhat.com/security/cve/CVE-2025-38733'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2393520'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2025-38733'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2025-38733'
  - url: >-
      https://lore.kernel.org/linux-cve-announce/2025090543-CVE-2025-38733-65a1@gregkh/T
  - url: 'https://git.kernel.org/stable/c/30bf5728bb217a6d1ba73f44094c9b9c6bc9a567'
  - url: 'https://git.kernel.org/stable/c/1d7864acd497cb468a998d44631f84896f885e85'
  - url: 'https://git.kernel.org/stable/c/93f616ff870a1fb7e84d472cad0af651b18f9f87'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
  - score-dispute
epss: 0.00166
epssPercentile: 0.05764
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-15T21:53:03.211075Z'
scores:
  vendor: 5.5
  cna: 7.8
ingestedAt: '2026-10-15T22:48:25.519Z'
---

## Overview

A flaw was found in the Linux kernel. Due to an incorrect identity mapping of the lowcore, a critical memory region, NULL pointer accesses may succeed instead of causing an exception. This vulnerability allows a local attacker to cause a Denial of Service (DoS) by triggering a system crash.

## Vendor advisories

- **Red Hat VEX** · Low · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9 · updated 2026-10-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-38733.json)

**kernel: Linux kernel: Denial of Service due to incorrect lowcore memory mapping** — rated Low by Red Hat. Released 2025-09-05, updated 2026-10-16.

Affected:

- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 9

No fix planned:

- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 9

Not affected:

- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8

## Remediation

Fix deferred

Workarounds / mitigations:

- Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.