---
id: CVE-2026-81007
title: 'ipmi: ipmb: validate write message length'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ipmi: ipmb: validate write message length

  ipmb_write() read message fields before validating the length byte.

  A zero or short write can read uninitialized stack bytes…
severity: high
cvss: 7.1
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H'
cvssSource: cna
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 51bd6f291583684f495ea498984dfc22049d7fd2 <
    8990c7f6bfc1e7689b7012a7d4d0efb9f07a9c89
  - >-
    Linux >= 51bd6f291583684f495ea498984dfc22049d7fd2 <
    94f8d20153e348c79bc14dc25f873470518892da
  - >-
    Linux >= 51bd6f291583684f495ea498984dfc22049d7fd2 <
    e527cd4e80066e1ed070fdc7c705bde340cdcc62
  - >-
    Linux >= 51bd6f291583684f495ea498984dfc22049d7fd2 <
    7d66d54b974cff0a959e188af844d2d110422767
  - >-
    Linux >= 51bd6f291583684f495ea498984dfc22049d7fd2 <
    60939bcda6f3f104ef456fdbf3cc5733c0720fb1
  - >-
    Linux >= 51bd6f291583684f495ea498984dfc22049d7fd2 <
    5719431ca2b5fa26560bb38f6202f8b97fa3bbb0
  - >-
    Linux >= 51bd6f291583684f495ea498984dfc22049d7fd2 <
    a84c6e3d188f2c6e674910929eb790634299d6d5
  - >-
    Linux >= 51bd6f291583684f495ea498984dfc22049d7fd2 <
    53637506884dbd5c91a89b1a3547d99d80f8ed2c
  - Linux 5.3
published: '2026-09-11'
updated: '2026-09-14'
sourceUpdated: '2026-09-14T11:59:40.685Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-81007'
references:
  - url: 'https://git.kernel.org/stable/c/8990c7f6bfc1e7689b7012a7d4d0efb9f07a9c89'
  - url: 'https://git.kernel.org/stable/c/94f8d20153e348c79bc14dc25f873470518892da'
  - url: 'https://git.kernel.org/stable/c/e527cd4e80066e1ed070fdc7c705bde340cdcc62'
  - url: 'https://git.kernel.org/stable/c/7d66d54b974cff0a959e188af844d2d110422767'
  - url: 'https://git.kernel.org/stable/c/60939bcda6f3f104ef456fdbf3cc5733c0720fb1'
  - url: 'https://git.kernel.org/stable/c/5719431ca2b5fa26560bb38f6202f8b97fa3bbb0'
  - url: 'https://git.kernel.org/stable/c/a84c6e3d188f2c6e674910929eb790634299d6d5'
  - url: 'https://git.kernel.org/stable/c/53637506884dbd5c91a89b1a3547d99d80f8ed2c'
tags:
  - cve.org
epss: 0.00126
epssPercentile: 0.02587
ingestedAt: '2026-09-14T15:23:07.454Z'
---

## Overview

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

ipmi: ipmb: validate write message length

ipmb_write() read message fields before validating the length byte.

A zero or short write can read uninitialized stack bytes.

A length smaller than the SMBus header underflows the block write length.

Require a non-empty buffer and the minimum IPMB request length.

Also require the length byte plus payload before parsing the message.

## Affected

- `Linux >= 51bd6f291583684f495ea498984dfc22049d7fd2 < 8990c7f6bfc1e7689b7012a7d4d0efb9f07a9c89`
- `Linux >= 51bd6f291583684f495ea498984dfc22049d7fd2 < 94f8d20153e348c79bc14dc25f873470518892da`
- `Linux >= 51bd6f291583684f495ea498984dfc22049d7fd2 < e527cd4e80066e1ed070fdc7c705bde340cdcc62`
- `Linux >= 51bd6f291583684f495ea498984dfc22049d7fd2 < 7d66d54b974cff0a959e188af844d2d110422767`
- `Linux >= 51bd6f291583684f495ea498984dfc22049d7fd2 < 60939bcda6f3f104ef456fdbf3cc5733c0720fb1`
- `Linux >= 51bd6f291583684f495ea498984dfc22049d7fd2 < 5719431ca2b5fa26560bb38f6202f8b97fa3bbb0`
- `Linux >= 51bd6f291583684f495ea498984dfc22049d7fd2 < a84c6e3d188f2c6e674910929eb790634299d6d5`
- `Linux >= 51bd6f291583684f495ea498984dfc22049d7fd2 < 53637506884dbd5c91a89b1a3547d99d80f8ed2c`
- `Linux 5.3`

## Remediation

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