---
id: CVE-2026-89502
title: >-
  kernel: ring-buffer: Free cpu_buffer::free_page with subbuf_order
  (CVE-2026-89502)
summary: >-
  A flaw was found in the Linux kernel's ring-buffer component. When sub-buffers
  are configured with a specific memory allocation order greater than zero, the
  system attempts to free a memory page using an incorrect size. This memory
  managem…
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-763
vendor: Red Hat
product: Red Hat Enterprise Linux 10
affected:
  - enterprise_linux 10
published: '2026-09-11'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T04:59:58+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89502.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89502.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-89502'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532342'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-89502'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89502'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89502.mbox
  - url: 'https://git.kernel.org/stable/c/234b1a72e9706fe20c08c96f4374ec8e83b934cb'
  - url: 'https://git.kernel.org/stable/c/77275ccea06eaf297e8e6ac3fc830cb72086379a'
  - url: 'https://git.kernel.org/stable/c/81063bbb16c4fcf0136c9117d5e49d3621dd6a1e'
  - url: 'https://git.kernel.org/stable/c/8c1ecdcdea738efe0494af908f12c0ae3a97fffa'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
epss: 0.00209
epssPercentile: 0.09819
ingestedAt: '2026-09-14T11:11:19.887Z'
---

## Overview

A flaw was found in the Linux kernel's ring-buffer component. When sub-buffers are configured with a specific memory allocation order greater than zero, the system attempts to free a memory page using an incorrect size. This memory management error can lead to memory corruption, potentially allowing a local attacker to escalate privileges or cause a system crash (Denial of Service).

## Vendor advisories

- **Red Hat VEX** · Low · affected: Red Hat Enterprise Linux 10 · no fix planned: Red Hat Enterprise Linux 10 · updated 2026-09-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89502.json)

**kernel: ring-buffer: Free cpu_buffer::free_page with subbuf_order** — rated Low by Red Hat. Released 2026-09-11, updated 2026-09-16.

Affected:

- Red Hat Enterprise Linux 10

No fix planned:

- Red Hat Enterprise Linux 10

Not affected:

- 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

Fix deferred