---
id: CVE-2026-102858
title: >-
  Heap-based buffer overflow in Microsoft Office OneNote allows an unauthorized
  attacker to execute code over a network.
summary: >-
  Heap-based buffer overflow in Microsoft Office OneNote allows an unauthorized
  attacker to execute code over a network.
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'
cwe:
  - CWE-122
vendor: microsoft
product: microsoft_365
affected:
  - microsoft_365
  - office_2021
  - office_2024
published: '2026-10-13'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T21:17:00.603'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-102858'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-102858'
    label: secure@microsoft.com
tags:
  - nvd
  - cve.org
epss: 0.00859
epssPercentile: 0.58268
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-13T21:14:27.548257Z'
ingestedAt: '2026-10-13T19:43:28.896Z'
---

## Overview

Heap-based buffer overflow in Microsoft Office OneNote allows an unauthorized attacker to execute code over a network.

## Affected

- `microsoft_365`
- `office_2021`
- `office_2024`

## Remediation

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