---
id: CVE-2026-97523
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  mptcp: close race between scheduler and state change

  The mptcp scheduler may race with subflow sockets state change: data
  transmission on the selected socket may fail …
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  mptcp: close race between scheduler and state change

  The mptcp scheduler may race with subflow sockets state change: data
  transmission on the selected socket may fail …
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-369
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= fb9c73ef2ac2ec816efdc8b9267bc04e1369c20b <
    d74b2e26b54a7dae1d87c1f19ae0d6db500e5e03
  - >-
    Linux >= c886d70286bf3ad411eb3d689328a67f7102c6ae <
    5883ae880f51edc4b1484e787473b865b6159ead
  - >-
    Linux >= c886d70286bf3ad411eb3d689328a67f7102c6ae <
    0a926b5df8efdfbac07e2fb7fafb21849a2ad9c0
  - >-
    Linux >= c886d70286bf3ad411eb3d689328a67f7102c6ae <
    8f11430d51ff8365bc51b670bc3002b65ae4c6b7
  - >-
    Linux >= c886d70286bf3ad411eb3d689328a67f7102c6ae <
    a09c87abf10a0a7e203137c75b5381aa63d9b31d
  - >-
    Linux >= c886d70286bf3ad411eb3d689328a67f7102c6ae <
    4c856f3c151a2f3fa237caa651c44015916ca584
  - >-
    Linux >= c886d70286bf3ad411eb3d689328a67f7102c6ae <
    42064de57fb83231fcc89663a94885f228a1ee53
  - Linux 8caf5c15b5288d52d9c89374d6c10fa32ee84ec5
  - Linux >= 5.15.190 < 5.15.222
  - Linux >= 5.19.4 < 5.20
  - Linux 6.0
published: '2026-09-25'
updated: '2026-10-03'
sourceUpdated: '2026-10-03T11:18:01.167'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-97523'
references:
  - url: 'https://git.kernel.org/stable/c/0a926b5df8efdfbac07e2fb7fafb21849a2ad9c0'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/42064de57fb83231fcc89663a94885f228a1ee53'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/4c856f3c151a2f3fa237caa651c44015916ca584'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/5883ae880f51edc4b1484e787473b865b6159ead'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/8f11430d51ff8365bc51b670bc3002b65ae4c6b7'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/a09c87abf10a0a7e203137c75b5381aa63d9b31d'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/d74b2e26b54a7dae1d87c1f19ae0d6db500e5e03'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-97523.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-97523'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2541112'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-97523'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-97523'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-97523.mbox
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
  - score-dispute
epss: 0.00709
epssPercentile: 0.53282
scores:
  nvd: 7.5
  vendor: 5.5
  cna: 7.5
ingestedAt: '2026-09-25T11:06:38.927Z'
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

mptcp: close race between scheduler and state change

The mptcp scheduler may race with subflow sockets state change: data
transmission on the selected socket may fail and a later release could
try to use mss_now reset to 0 for a divide operation.

Address the issue by explicitly checking for the critical scenario.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, 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 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-10-17 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-97523.json)