---
id: CVE-2025-21687
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  vfio/platform: check the bounds of read/write syscalls

  count and offset are passed from user space and not checked, only
  offset is capped to 40 bits, which can be used…
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  vfio/platform: check the bounds of read/write syscalls

  count and offset are passed from user space and not checked, only
  offset is capped to 40 bits, which can be used…
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-125
  - CWE-787
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 4.1, < 5.4.290'
  - 'linux_kernel >= 5.5, < 5.10.234'
  - 'linux_kernel >= 5.11, < 5.15.178'
  - 'linux_kernel >= 5.16, < 6.1.128'
  - 'linux_kernel >= 6.2, < 6.6.75'
  - 'linux_kernel >= 6.7, < 6.12.12'
  - linux_kernel = 6.13
patched:
  - linux_kernel 6.12.12
published: '2025-02-10'
updated: '2026-07-30'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-21687'
references:
  - url: 'https://git.kernel.org/stable/c/1485932496a1b025235af8aa1e21988d6b7ccd54'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/665cfd1083866f87301bbd232cb8ba48dcf4acce'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/6bcb8a5b70b80143db9bf12dfa7d53636f824d53'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/92340e6c5122d823ad064984ef7513eba9204048'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/9377cdc118cf327248f1a9dde7b87de067681dc9'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/a20fcaa230f7472456d12cf761ed13938e320ac3'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/c981c32c38af80737a2fedc16e270546d139ccdd'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ce9ff21ea89d191e477a02ad7eabf4f996b80a69'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/d19a8650fd3d7aed8d1af1d9a77f979a8430eba1'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/ed81d82bb6e9df3a137f2c343ed689e6c68268ef'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f21636f24b6786c8b13f1af4319fa75ffcf17f38'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/f65ce06387f8c1fb54bd59e18a8428248ec68eaf'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
epss: 0.00235
epssPercentile: 0.12883
ingestedAt: '2026-07-30T06:53:09.213Z'
---

## Overview

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

vfio/platform: check the bounds of read/write syscalls

count and offset are passed from user space and not checked, only
offset is capped to 40 bits, which can be used to read/write out of
bounds of the device.

## Affected

- `linux_kernel >= 4.1, < 5.4.290`
- `linux_kernel >= 5.5, < 5.10.234`
- `linux_kernel >= 5.11, < 5.15.178`
- `linux_kernel >= 5.16, < 6.1.128`
- `linux_kernel >= 6.2, < 6.6.75`
- `linux_kernel >= 6.7, < 6.12.12`
- `linux_kernel = 6.13`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.12.12`