---
id: CVE-2026-89701
title: 'kernel: nfsd: validate nseconds in TIME_DELEG decode paths (CVE-2026-89701)'
summary: >-
  A flaw was found in the Linux kernel's Network File System Daemon (nfsd). The
  TIME_DELEG_ACCESS and TIME_DELEG_MODIFY decode paths do not properly validate
  the nanosecond (nseconds) value in timestamps. This allows a remote attacker
  to pro…
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-1284
vendor: Red Hat
product: Red Hat Enterprise Linux 10
affected:
  - enterprise_linux 10
  - enterprise_linux 6
published: '2026-09-11'
updated: '2026-09-21'
sourceUpdated: '2026-09-21T14:05:32+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89701.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89701.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-89701'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532154'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-89701'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89701'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89701.mbox
  - url: 'https://git.kernel.org/stable/c/0f4a767340fad392bd656115b8752005518c9065'
  - url: 'https://git.kernel.org/stable/c/5eb489831a9fd4754f4baf26e6989efb66ce104c'
  - url: 'https://git.kernel.org/stable/c/7e7b93da7fa2e77f977096251899d1410986adf6'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
epss: 0.00166
epssPercentile: 0.0625
ingestedAt: '2026-09-14T11:11:19.885Z'
---

## Overview

A flaw was found in the Linux kernel's Network File System Daemon (nfsd). The TIME_DELEG_ACCESS and TIME_DELEG_MODIFY decode paths do not properly validate the nanosecond (nseconds) value in timestamps. This allows a remote attacker to provide a malformed timestamp, which can then be written to disk, potentially leading to data integrity issues or unexpected system behavior.

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10 · updated 2026-09-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89701.json)

**kernel: nfsd: validate nseconds in TIME_DELEG decode paths** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-21.

Affected:

- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 6

No fix planned:

- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 10

Not affected:

- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4

## Remediation

Out of support scope