---
id: CVE-2021-38646
title: >-
  Microsoft Office Access Connectivity Engine Remote Code Execution
  Vulnerability
summary: >-
  Microsoft Office Access Connectivity Engine 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
  - office = 2013
  - office_2016
  - office_2019
published: '2021-09-15'
updated: '2026-08-10'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2021-38646'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-38646'
    label: secure@microsoft.com
  - url: >-
      https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-38646
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-38646
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - kev
  - in-the-wild
epss: 0.07987
epssPercentile: 0.94548
kev: true
kevDateAdded: '2022-03-28'
kevDueDate: '2022-04-18'
kevRansomware: true
exploited: true
ingestedAt: '2026-08-11T16:47:01.290Z'
---

## Overview

Microsoft Office Access Connectivity Engine Remote Code Execution Vulnerability

## Affected

- `365_apps`
- `office = 2013`
- `office_2016`
- `office_2019`

## Remediation

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