---
id: CVE-2025-38058
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  __legitimize_mnt(): check for MNT_SYNC_UMOUNT should be under mount_lock

  ..
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  __legitimize_mnt(): check for MNT_SYNC_UMOUNT should be under mount_lock

  ... or we risk stealing final mntput from sync umount - raising mnt_count
  after umount(2) has …
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-667
vendor: linux
product: linux_kernel
affected:
  - linux_kernel < 5.4.294
  - 'linux_kernel >= 5.5, < 5.10.238'
  - 'linux_kernel >= 5.11, < 5.15.185'
  - 'linux_kernel >= 5.16, < 6.1.141'
  - 'linux_kernel >= 6.2, < 6.6.93'
  - 'linux_kernel >= 6.7, < 6.12.31'
  - 'linux_kernel >= 6.13, < 6.14.9'
  - linux_kernel = 6.15
  - debian_linux = 11.0
patched:
  - linux_kernel 6.14.9
published: '2025-06-18'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T22:18:25.120'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-38058'
references:
  - url: 'https://git.kernel.org/stable/c/250cf3693060a5f803c5f1ddc082bb06b16112a9'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/628fb00195ce21a90cf9e4e3d105cd9e58f77b40'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/8cafd7266fa02e0863bacbf872fe635c0b9725eb'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/9b0915e72b3cf52474dcee0b24a2f99d93e604a3'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b55996939c71a3e1a38f3cdc6a8859797efc9083'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/b89eb56a378b7b2c1176787fc228d0a57172bdd5'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/d8ece4ced3b051e656c77180df2e69e19e24edc1'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f6d45fd92f62845cbd1eb5128fd8f0ed7d0c5a42'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-082556.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
  - cve.org
epss: 0.00169
epssPercentile: 0.06235
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-15T21:46:56.186006Z'
ingestedAt: '2026-10-15T05:52:46.097Z'
---

## Overview

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

__legitimize_mnt(): check for MNT_SYNC_UMOUNT should be under mount_lock

... or we risk stealing final mntput from sync umount - raising mnt_count
after umount(2) has verified that victim is not busy, but before it
has set MNT_SYNC_UMOUNT; in that case __legitimize_mnt() doesn't see
that it's safe to quietly undo mnt_count increment and leaves dropping
the reference to caller, where it'll be a full-blown mntput().

Check under mount_lock is needed; leaving the current one done before
taking that makes no sense - it's nowhere near common enough to bother
with.

## Affected

- `linux_kernel < 5.4.294`
- `linux_kernel >= 5.5, < 5.10.238`
- `linux_kernel >= 5.11, < 5.15.185`
- `linux_kernel >= 5.16, < 6.1.141`
- `linux_kernel >= 6.2, < 6.6.93`
- `linux_kernel >= 6.7, < 6.12.31`
- `linux_kernel >= 6.13, < 6.14.9`
- `linux_kernel = 6.15`
- `debian_linux = 11.0`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.14.9`