---
id: CVE-2023-3865
title: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ksmbd: fix out-of-bound read in smb2_write

  ksmbd_smb2_check_message doesn't validate hdr->NextCommand
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ksmbd: fix out-of-bound read in smb2_write

  ksmbd_smb2_check_message doesn't validate hdr->NextCommand. If
  ->NextCommand is bigger than Offset + Length of smb2 write, I…
severity: high
cvss: 8.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H'
cwe:
  - CWE-125
vendor: linux
product: linux_kernel
affected:
  - 'linux_kernel >= 5.15, < 5.15.121'
  - 'linux_kernel >= 5.16, < 6.1.36'
  - 'linux_kernel >= 6.2, < 6.3.10'
  - linux_kernel = 6.4
patched:
  - linux_kernel 6.3.10
published: '2025-08-16'
updated: '2026-08-15'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2023-3865'
references:
  - url: 'https://git.kernel.org/stable/c/3813eee5154d6a4c5875cb4444cb2b63bac8947f'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/58a9c41064df27632e780c5a3ae3e0e4284957d1'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/5fe7f7b78290638806211046a99f031ff26164e1'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
  - url: 'https://git.kernel.org/stable/c/c86211159bc3178b891e0d60e586a32c7b6a231b'
    label: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
tags:
  - nvd
epss: 0.00602
epssPercentile: 0.46496
ingestedAt: '2026-08-15T13:26:45.277Z'
---

## Overview

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

ksmbd: fix out-of-bound read in smb2_write

ksmbd_smb2_check_message doesn't validate hdr->NextCommand. If
->NextCommand is bigger than Offset + Length of smb2 write, It will
allow oversized smb2 write length. It will cause OOB read in smb2_write.

## Affected

- `linux_kernel >= 5.15, < 5.15.121`
- `linux_kernel >= 5.16, < 6.1.36`
- `linux_kernel >= 6.2, < 6.3.10`
- `linux_kernel = 6.4`

## Remediation

Upgrade past the affected range:

- `linux_kernel 6.3.10`