---
id: CVE-2026-89649
title: 'kernel: ceph: bound xattr value length in __build_xattrs() (CVE-2026-89649)'
summary: >-
  A flaw was found in the Linux kernel's Ceph file system (CephFS) component. A
  malicious or compromised metadata server can manipulate the length of an
  extended attribute (xattr) value, causing the system to read beyond the
  intended memory …
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-125
vendor: Red Hat
product: Red Hat Enterprise Linux 9
affected:
  - enterprise_linux 10
  - enterprise_linux 7
  - enterprise_linux 8
  - enterprise_linux 9
  - openshift_container_platform 4
published: '2026-09-11'
updated: '2026-09-18'
sourceUpdated: '2026-09-18T20:12:31+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89649.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89649.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-89649'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532268'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-89649'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89649'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89649.mbox
  - url: 'https://git.kernel.org/stable/c/848b80ca6b410f350d08b8ac19a00ef88223f2ea'
  - url: 'https://git.kernel.org/stable/c/01e3f19c301d492e12f16b3b463ac14d7cf3ebe7'
  - url: 'https://git.kernel.org/stable/c/cb0cd79ae80476d1bc06bd9678484b6736f19588'
  - url: 'https://git.kernel.org/stable/c/61f085cb8976c9cebc90e1a8933e4cc1ad8b0fce'
  - url: 'https://git.kernel.org/stable/c/38be2f3c41ecaba58bb92dc16603e09ba9fd64f1'
  - url: 'https://git.kernel.org/stable/c/1dd356310b1660215f9a3626580bf8b363ef981e'
  - url: 'https://git.kernel.org/stable/c/b12b3320c81fd72ab36388fb2445fec9c3038f10'
  - url: 'https://git.kernel.org/stable/c/68d541754d6cd3bb98d1fd8314f57e5eb533557d'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
  - score-dispute
epss: 0.00669
epssPercentile: 0.50539
scores:
  vendor: 7
  cna: 9.1
ingestedAt: '2026-09-14T15:23:07.450Z'
---

## Overview

A flaw was found in the Linux kernel's Ceph file system (CephFS) component. A malicious or compromised metadata server can manipulate the length of an extended attribute (xattr) value, causing the system to read beyond the intended memory boundary. This out-of-bounds read allows a local user to access sensitive data from the kernel's memory, leading to information disclosure.

## Vendor advisories

- **Red Hat VEX** · Moderate · 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 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, … · updated 2026-09-18 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89649.json)

**kernel: ceph: bound xattr value length in __build_xattrs()** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-18.

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

No fix planned:

- 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

Not affected:

- Red Hat Enterprise Linux 6

## Remediation

Affected