---
id: CVE-2026-89743
title: 'kernel: misc: nsm: bound the device-reported response length (CVE-2026-89743)'
summary: >-
  A flaw was found in the Linux kernel's Network Shared Memory (NSM) component.
  A malicious or buggy backend can report a response length larger than the
  allocated buffer. This can lead to an out-of-bounds read, disclosing adjacent
  kernel me…
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-125
vendor: Red Hat
product: Red Hat OpenShift Container Platform 4
affected:
  - openshift_container_platform 4
published: '2026-09-11'
updated: '2026-09-21'
sourceUpdated: '2026-09-21T17:36:57+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89743.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89743.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-89743'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532206'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-89743'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89743'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89743.mbox
  - url: 'https://git.kernel.org/stable/c/29e634a18957acda11383a15ab98a91c4ae9e294'
  - url: 'https://git.kernel.org/stable/c/2aa0fb9c96f894a9c179a48e7522ea6705800adf'
  - url: 'https://git.kernel.org/stable/c/339f19b9a6171289b0e797deb8bda80b9a1fcc30'
  - url: 'https://git.kernel.org/stable/c/808e530654a5354e6df78863a5d61e4d44e67235'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
epss: 0.0019
epssPercentile: 0.07738
scores:
  vendor: 6.3
  cna: 7.7
ingestedAt: '2026-09-14T15:23:07.472Z'
---

## Overview

A flaw was found in the Linux kernel's Network Shared Memory (NSM) component. A malicious or buggy backend can report a response length larger than the allocated buffer. This can lead to an out-of-bounds read, disclosing adjacent kernel memory to user space. This vulnerability results in information disclosure.

## Vendor advisories

- **Red Hat VEX** · Moderate · updated 2026-09-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89743.json)

**kernel: misc: nsm: bound the device-reported response length** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-21.

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.