---
id: CVE-2026-89688
title: >-
  kernel: nfsd: drop the stateid, not the stateowner, on seqid_op replay retry
  (CVE-2026-89688)
summary: >-
  A flaw was found in the Linux kernel's nfsd component. During a `seqid_op`
  replay retry, the system incorrectly handles reference counts for stateowners,
  leading to a reference count underflow and a use-after-free vulnerability.
  This issue…
severity: medium
cvss: 5.3
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H'
cvssSource: vendor
cwe:
  - CWE-416
  - CWE-825
vendor: Red Hat
product: Red Hat Enterprise Linux 9
affected:
  - enterprise_linux 10
  - enterprise_linux 6
  - enterprise_linux 9
  - openshift_container_platform 4
published: '2026-09-11'
updated: '2026-10-21'
sourceUpdated: '2026-10-21T10:02:18+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89688.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89688.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-89688'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532337'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-89688'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89688'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89688.mbox
  - url: 'https://kernelcve.org/list/?q=CVE-2026-89688'
  - url: 'https://git.kernel.org/stable/c/69ed78b6b947c9257213164678b4edf17533093b'
  - url: 'https://git.kernel.org/stable/c/00843074d9b84824552c9679d423d29500ca5de0'
  - url: 'https://git.kernel.org/stable/c/f7cb90ddc021747fc9abfd4cf5252d425fd34eec'
  - url: 'https://git.kernel.org/stable/c/5e4627d3513e60accfce9d5f4c7fa95251ef93d6'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
  - score-dispute
epss: 0.00736
epssPercentile: 0.54256
scores:
  vendor: 7
  cna: 9.8
ingestedAt: '2026-09-14T15:23:07.473Z'
---

## Overview

A flaw was found in the Linux kernel's nfsd component. During a `seqid_op` replay retry, the system incorrectly handles reference counts for stateowners, leading to a reference count underflow and a use-after-free vulnerability. This issue could allow an attacker to potentially cause a denial of service or execute arbitrary code.

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-10-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89688.json)

**kernel: nfsd: drop the stateid, not the stateowner, on seqid_op replay retry** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-10-21.

Affected:

- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4

No fix planned:

- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4

Not affected:

- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat OpenShift Container Platform 4

## Remediation

Out of support scope

Workarounds / mitigations:

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