How severe is CVE-2021-38646?

High severity. CVSS v3 base score is 7.8 out of 10.

Is CVE-2021-38646 known to be exploited?

Yes. CVE-2021-38646 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-03-28), indicating it is being actively exploited. 5 public proof-of-concept repositories are indexed.

Vulnerability in Microsoft 365 Apps For Enterprise

CVE-2021-38646

Microsoft Office Access Connectivity Engine Remote Code Execution Vulnerability

EPSS: 0.509 (97.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C.

Affected products

Microsoft 365 Apps For Enterprise — versions 16.0.1
Microsoft Office 2013 Service Pack 1 — versions 15.0.0
Microsoft Office 2016 — versions 16.0.0
Microsoft Office 2019 — versions 19.0.0

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2022-03-28. CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: 2022-04-18.

Required action: Apply updates per vendor instructions.

Known ransomware campaign use: yes.

Public proof-of-concept exploits

References

portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-38646 (x_refsource_MISC)

Frequently asked questions

What is CVE-2021-38646?: CVE-2021-38646 is a high-severity vulnerability in Microsoft 365 Apps For Enterprise. CVSS score: 7.8/10. Published 2021-09-15.
How severe is CVE-2021-38646?: High severity. CVSS v3 base score is 7.8 out of 10.
Is CVE-2021-38646 known to be exploited?: Yes. CVE-2021-38646 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-03-28), indicating it is being actively exploited. 5 public proof-of-concept repositories are indexed.