---
id: CVE-2026-89767
title: >-
  kernel: ovl: fix double end_creating() on the casefold-mismatch path
  (CVE-2026-89767)
summary: >-
  A flaw was found in the Linux kernel's overlay file system (overlayfs). An
  unprivileged local user can trigger a specific error condition during the
  creation of a new directory. This error causes the system to incorrectly
  release a lock on…
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-1341
vendor: Red Hat
product: Red Hat OpenShift Container Platform 4
affected:
  - openshift_container_platform 4
published: '2026-09-11'
updated: '2026-09-15'
sourceUpdated: '2026-09-15T10:22:20+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89767.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89767.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-89767'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532416'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-89767'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89767'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89767.mbox
  - url: 'https://git.kernel.org/stable/c/077ab8985ee278c3d8618182d335b0f0cd919e16'
  - url: 'https://git.kernel.org/stable/c/2fa220bc0f84597cb6de665e5b5021c5901ddf00'
  - url: 'https://git.kernel.org/stable/c/b1aa8ab78a8e87aee9e306971465408e059f839a'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
  - score-dispute
epss: 0.00151
epssPercentile: 0.04646
scores:
  vendor: 5.5
  cna: 7.8
ingestedAt: '2026-09-14T15:23:07.472Z'
---

## Overview

A flaw was found in the Linux kernel's overlay file system (overlayfs). An unprivileged local user can trigger a specific error condition during the creation of a new directory. This error causes the system to incorrectly release a lock on the parent directory and a reference to the new directory entry twice. This double release can lead to subsequent attempts to create directories under the same parent to become unresponsive, effectively causing a denial of service (DoS) for those operations.

## Vendor advisories

- **Red Hat VEX** · Moderate · updated 2026-09-15 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89767.json)

**kernel: ovl: fix double end_creating() on the casefold-mismatch path** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-15.

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.