CVE-2021-40479

Name: CVE-2021-40479
Creator: NVD / NIST
Published: 2021-10-13T01:15:11.64+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.8/10EPSS 2.18%

Last modified Jun 17, 2026

CVE-2021-40479 is a high-severity vulnerability rated 7.8/10 on the CVSS scale. Microsoft Excel Remote Code Execution Vulnerability. EPSS estimates a 2.18% chance of exploitation in the next 30 days.

Description

Microsoft Excel Remote Code Execution Vulnerability

Metrics

CVSS 3.1

7.8/10

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

EPSS Probability

2.18%

80.0th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions	Update
Microsoft	365 Apps	All versions	—
Microsoft	Office	2013	Sp1
Microsoft	Office	2016	—
Microsoft	Office	2019	—
Microsoft	Office Long Term Servicing Channel	2021	—

References

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-40479Patch, Vendor Advisory
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-40479Patch, Vendor Advisory

Timeline

Published: Oct 13, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-40479?

Microsoft Excel Remote Code Execution Vulnerability

How severe is CVE-2021-40479?

CVE-2021-40479 has a CVSS score of 7.8/10 (HIGH severity). The EPSS model estimates a 2.18% probability of exploitation in the next 30 days.

How do I fix CVE-2021-40479?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-40479?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST