---
id: CVE-2021-34501
title: Microsoft Excel Remote Code Execution Vulnerability
summary: Microsoft Excel Remote Code Execution Vulnerability
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'
vendor: microsoft
product: 365_apps
affected:
  - 365_apps
  - excel = 2013
  - excel = 2016
  - office = 2019
  - office_online_server
published: '2021-07-14'
updated: '2026-08-10'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2021-34501'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-34501'
    label: secure@microsoft.com
  - url: >-
      https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-34501
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://www.zerodayinitiative.com/advisories/ZDI-21-969/'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
epss: 0.51392
epssPercentile: 0.98904
zeroDay: true
ingestedAt: '2026-08-10T16:41:16.931Z'
---

## Overview

Microsoft Excel Remote Code Execution Vulnerability

## Affected

- `365_apps`
- `excel = 2013`
- `excel = 2016`
- `office = 2019`
- `office_online_server`

## Remediation

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