---
title: "CVE-2026-90149: Linux Kernel - Denial of Service"
description: "Linux kernel contains a NULL dereference vulnerability in NFSv4/flexfiles caused by improper handling of NFSv4.0 data servers without sessions, letting attackers cause kernel oops during I/O operations, exploit requires use of NFSv4.0 data servers."
url: https://panop.io/threat-heartbeat/CVE-2026-90149/
---

# CVE-2026-90149 Linux Kernel - Denial of Service

Linux kernel contains a NULL dereference vulnerability in NFSv4/flexfiles caused by improper handling of NFSv4.0 data servers without sessions, letting attackers cause kernel oops during I/O operations, exploit requires use of NFSv4.0 data servers.

CVSS base score 7.5 /10

High

CISA KEV

Not listed

Public exploit

None known

Authentication

Not required

EPSS

0.61% chance of exploitation in 30 days

[View the NVD record ↗](https://nvd.nist.gov/vuln/detail/CVE-2026-90149)

## Details

Type

Denial of Service

Impact

Denial Of Service

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Published

17 September 2026

Updated

15 October 2026

## Vendor fix

Update to the latest Linux kernel version with the fix for NFSv4/flexfiles NULL dereference.

Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them.

## References

- [https://nvd.nist.gov/vuln/detail/CVE-2026-90149](https://nvd.nist.gov/vuln/detail/CVE-2026-90149)
- [https://git.kernel.org/stable/c/163c16e01f53fc8eb8d0f3484ae6c382265ecbbd](https://git.kernel.org/stable/c/163c16e01f53fc8eb8d0f3484ae6c382265ecbbd)
- [https://git.kernel.org/stable/c/2b03ebbf8d5e8f6af4ecd6c65375232dd1ec32cc](https://git.kernel.org/stable/c/2b03ebbf8d5e8f6af4ecd6c65375232dd1ec32cc)
- [https://git.kernel.org/stable/c/436a214514e24103159aea455147d58b44a8a585](https://git.kernel.org/stable/c/436a214514e24103159aea455147d58b44a8a585)

[← All CVEs](https://panop.io/threat-heartbeat/)

## What this record can't tell you

- Whether you run the affected software, and where
- Whether an attacker can actually reach and exploit it
- The misconfigurations that never get a CVE number
- What it would cost the business, ranked into what to fix first

Panop answers these inside your environment, for this CVE and every other finding.

[Book a demo](https://panop.io/demo)