# CVE-2021-38646: Microsoft Office Access Connectivity Engine Remote Code Execution Vulnerability

Source: https://junglewise.ai/threats/cve-2021-38646-microsoft-office-access-connectivity-engine-remote-code-execution  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2022-03-28. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-2021-38646 · Severity: critical · CVSS 7.8 · Exploited in the wild · Published 2022-03-28

The Microsoft Office Access Connectivity Engine contains a vulnerability that allows for remote code execution when a user opens a specially crafted file. The flaw stems from an unspecified memory corruption issue within the engine used by various Microsoft Office products.

Technologies: [Microsoft Office](https://junglewise.ai/threats/technologies/office). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2021-38646 exploited in the wild?** Yes. CVE-2021-38646 is known to be exploited in the wild, first recorded on 28 March 2022. Treat it as urgent.

**How severe is CVE-2021-38646?** Critical severity, with a CVSS score of 7.8, published 28 March 2022.

**Which products and versions are affected?** Microsoft Office 2013 Service Pack 1; Microsoft Office 2016; Microsoft Office 2019; Microsoft Microsoft 365 Apps for Enterprise; and 1 more.

**Is there a fix for CVE-2021-38646?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2021-38646 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2021-38646?** Check whether you run Microsoft Office. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- Microsoft Office 2013 Service Pack 1
- Microsoft Office 2016
- Microsoft Office 2019
- Microsoft Microsoft 365 Apps for Enterprise
- Microsoft Office Access Connectivity Engine

## Timeline

- 2021-09-15: disclosed: NVD Published Date
- 2022-03-28: kev added: Added to CISA Known Exploited Vulnerabilities Catalog

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