CVE-2021-38646

Microsoft 365 Apps for Enterprise, Microsoft Office 2013 Service Pack 1, Microsoft Office 2016

Published 15 Sept 2021 · updated 10 Aug 2026 · Analyzed

7.8 High · CVSS 3.1, microsoft.com

Exploited in the wild

CISA added this to its Known Exploited Vulnerabilities catalog on 28 Mar 2022, with a remediation deadline of 18 Apr 2022 for US federal agencies. It has been used in ransomware campaigns.

Required action: Apply updates per vendor instructions.

Description

Microsoft Office Access Connectivity Engine Remote Code Execution Vulnerability

References

msrc.microsoft.com/update-guide/vulnerability/CVE-2021-38646 · Patch, Vendor Advisory
portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-38646 · Patch, Vendor Advisory
www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-38646 · US Government Resource