CVE-2021-38646

Microsoft Office Access Connectivity Engine Remote Code Execution

7.8 HIGHActively exploited (CISA KEV)Used in ransomwareEPSS 7.99%

Published15 Sept 2021
Added to CISA KEV28 Mar 2022
Remediation due18 Apr 2022

Description

Microsoft Office Access Connectivity Engine Remote Code Execution Vulnerability

CVSS 3.1 breakdown

Attack vectorLocal

Attack complexityLow

Privileges requiredNone

User interactionRequired

ScopeUnchanged

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Affected products

Microsoft 365 Appsall versions

Microsoft Office2013

Microsoft Office 2016all versions

Microsoft Office 2019all versions

Remediation

No fixed version is recorded in the NVD data. Check the vendor advisory for the latest guidance.

Patch & vendor advisories

References

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

Frequently asked

Is CVE-2021-38646 being actively exploited?

Yes. CVE-2021-38646 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added 28 Mar 2022. It has been used in ransomware campaigns.

How severe is CVE-2021-38646?

CVE-2021-38646 has a CVSS 3.1 base score of 7.8, rated high. EPSS estimates a 7.99% probability of exploitation.

Which products are affected by CVE-2021-38646?

Affected products include Microsoft 365 Apps, Microsoft Office, Microsoft Office 2016, Microsoft Office 2019.

How do I fix CVE-2021-38646?

Apply the vendor's patch or advisory guidance, then verify no affected versions remain across your devices.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2021-38646 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. Because it is on the CISA KEV list, Secuno flags any affected asset as top-priority automatically. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

See how prioritisation works Book a demo

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.