---
id: CVE-2021-31206
title: Microsoft Exchange Server Remote Code Execution Vulnerability
summary: Microsoft Exchange Server Remote Code Execution Vulnerability
severity: high
cvss: 7.6
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:L'
vendor: microsoft
product: exchange_server
affected:
  - exchange_server = 2013
  - exchange_server = 2016
  - exchange_server = 2019
published: '2021-07-14'
updated: '2026-08-10'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2021-31206'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-31206'
    label: secure@microsoft.com
  - url: >-
      https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31206
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://www.zerodayinitiative.com/advisories/ZDI-21-826/'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
  - in-the-wild
epss: 0.13006
epssPercentile: 0.96191
exploited: true
zeroDay: true
ingestedAt: '2026-08-10T16:41:14.375Z'
---

## Overview

Microsoft Exchange Server Remote Code Execution Vulnerability

## Affected

- `exchange_server = 2013`
- `exchange_server = 2016`
- `exchange_server = 2019`

## Remediation

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