---
id: CVE-2025-40051
title: 'vhost: vringh: Modify the return value check'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  vhost: vringh: Modify the return value check

  The return value of copy_from_iter and copy_to_iter can't be negative,
  check whether the copied lengths are equal.
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'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 309bba39c945ac8ab8083ac05cd6cfe5822968e0 <
    db042925a5ab7a550b710addeadbf6f72e3a8a4b
  - >-
    Linux >= 309bba39c945ac8ab8083ac05cd6cfe5822968e0 <
    78dc7362662fedaa1928fb8e4f27401c8322905d
  - >-
    Linux >= 309bba39c945ac8ab8083ac05cd6cfe5822968e0 <
    baa37b1c7e29546f79c39bef0d18c4edc9f39bb1
  - >-
    Linux >= 309bba39c945ac8ab8083ac05cd6cfe5822968e0 <
    cfa0654402c06d086201a9ff167eb95da5844fc3
  - >-
    Linux >= 309bba39c945ac8ab8083ac05cd6cfe5822968e0 <
    82a8d0fda55b35361ee7f35b54fa2b66d7847d2b
  - Linux 6.0
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-15T21:56:30.680415Z'
published: '2025-10-28'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T22:02:36.974Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2025-40051'
references:
  - url: 'https://git.kernel.org/stable/c/db042925a5ab7a550b710addeadbf6f72e3a8a4b'
  - url: 'https://git.kernel.org/stable/c/78dc7362662fedaa1928fb8e4f27401c8322905d'
  - url: 'https://git.kernel.org/stable/c/baa37b1c7e29546f79c39bef0d18c4edc9f39bb1'
  - url: 'https://git.kernel.org/stable/c/cfa0654402c06d086201a9ff167eb95da5844fc3'
  - url: 'https://git.kernel.org/stable/c/82a8d0fda55b35361ee7f35b54fa2b66d7847d2b'
tags:
  - cve.org
epss: 0.00165
epssPercentile: 0.057
ingestedAt: '2026-10-15T22:48:25.539Z'
---

## Overview

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

vhost: vringh: Modify the return value check

The return value of copy_from_iter and copy_to_iter can't be negative,
check whether the copied lengths are equal.

## Affected

- `Linux >= 309bba39c945ac8ab8083ac05cd6cfe5822968e0 < db042925a5ab7a550b710addeadbf6f72e3a8a4b`
- `Linux >= 309bba39c945ac8ab8083ac05cd6cfe5822968e0 < 78dc7362662fedaa1928fb8e4f27401c8322905d`
- `Linux >= 309bba39c945ac8ab8083ac05cd6cfe5822968e0 < baa37b1c7e29546f79c39bef0d18c4edc9f39bb1`
- `Linux >= 309bba39c945ac8ab8083ac05cd6cfe5822968e0 < cfa0654402c06d086201a9ff167eb95da5844fc3`
- `Linux >= 309bba39c945ac8ab8083ac05cd6cfe5822968e0 < 82a8d0fda55b35361ee7f35b54fa2b66d7847d2b`
- `Linux 6.0`

## Remediation

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