CVE-2020-16929 — Microsoft Excel Remote Code Execution Vulnerability

Executive Summary

A remote code execution vulnerability exists in Microsoft Excel software when the software fails to properly handle objects in memory. An attacker who successfully exploited the vulnerability could run arbitrary code in the context of the current user. If the current user is logged on with administrative user rights, an attacker could take control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights. Exploitation of the vulnerability requires that a user open a specially crafted file with an affected version of Microsoft Excel. In an email attack scenario, an attacker could exploit the vulnerability by sending the specially crafted file to the user and convincing the user to open the file. In a web-based attack scenario, an attacker could host a website (or leverage a compromised website that accepts or hosts user-provided content) containing a specially crafted file designed to exploit the vulnerability. An attacker would have no way to force users to visit the website. Instead, an attacker would have to convince users to click a link, typically by way of an enticement in an email or instant message, and then convince them to open the specially crafted file. The security update addresses the vulnerability by correcting how Microsoft Excel handles objects in memory.

Overview

7.8

CVSS HIGH

Important

MS Severity

Not Exploited

MS Exploit Status

Less Likely

MS Exploit Likelihood

Category Remote Code Execution

Released Oct 13 2020

Last Updated Oct 13 2020

Publicly Disclosed No

CISA KEV Not Listed

Known Exploits None Known

EPSS Score 0.03424 — 0.8737 percentile

CVSS Vector

ATTACK VECTOR

Local

ATTACK COMPLEXITY

Low

PRIVILEGES REQUIRED

None

USER INTERACTION

Required

SCOPE

Unchanged

Temporal Score: 7.0

EPSS Score

0.03424

probability of exploitation in the next 30 days

0.8737 percentile - updated 2026-06-20

View on FIRST.org

Affected Products

26 affected products

Product	KB Article	Severity	Impact	Restart Required
Microsoft 365 Apps for Enterprise for 32-bit Systems	`Click to Run (Security Update)`	Important	Remote Code Execution	No
Microsoft 365 Apps for Enterprise for 64-bit Systems	`Click to Run (Security Update)`	Important	Remote Code Execution	No
Microsoft Excel 2010 Service Pack 2 (32-bit editions)	`4486707 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Excel 2010 Service Pack 2 (64-bit editions)	`4486707 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Excel 2013 RT Service Pack 1	`4486695 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Excel 2013 Service Pack 1 (32-bit editions)	`4486695 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Excel 2013 Service Pack 1 (64-bit editions)	`4486695 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Excel 2016 (32-bit edition)	`4486678 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Excel 2016 (64-bit edition)	`4486678 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Excel Web App 2010 Service Pack 2	`4462175 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Office 2010 Service Pack 2 (32-bit editions)	`4486700 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Office 2010 Service Pack 2 (64-bit editions)	`4486700 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Office 2013 RT Service Pack 1	`4486688 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Office 2013 Service Pack 1 (32-bit editions)	`4486688 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Office 2013 Service Pack 1 (64-bit editions)	`4486688 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Office 2016 (32-bit edition)	`4486682 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Office 2016 (64-bit edition)	`4486682 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Office 2016 for Mac	`Release Notes (Security Update)`	Important	Remote Code Execution	No
Microsoft Office 2019 for 32-bit editions	`Click to Run (Security Update)`	Important	Remote Code Execution	No
Microsoft Office 2019 for 64-bit editions	`Click to Run (Security Update)`	Important	Remote Code Execution	No
Microsoft Office 2019 for Mac	`Release Notes (Security Update)`	Important	Remote Code Execution	No
Microsoft Office Online Server	`4486674 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Office Web Apps 2010 Service Pack 2	`4462175 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Office Web Apps 2013 Service Pack 1	`4486689 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft SharePoint Enterprise Server 2013 Service Pack 1	`4486687 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft SharePoint Server 2010 Service Pack 2	`4484531 (Security Update)`	Important	Remote Code Execution	Maybe

Patches

13 patches

Article	Type	Restart
`Click to Run`	Security Update	No
`4486707`	Security Update	Maybe
`4486695`	Security Update	Maybe
`4486678`	Security Update	Maybe
`4462175`	Security Update	Maybe
`4486700`	Security Update	Maybe
`4486688`	Security Update	Maybe
`4486682`	Security Update	Maybe
`Release Notes`	Security Update	No
`4486674`	Security Update	Maybe
`4486689`	Security Update	Maybe
`4486687`	Security Update	Maybe
`4484531`	Security Update	Maybe

Known Exploits

No known exploits have been linked for this CVE yet. When available, exploit references will be sourced from public repositories and may be unverified, incomplete, or non-functional. Always review code carefully before use in any environment.

Acknowledgments

Trend Micro's Zero Day Initiative

References

MSRC Advisory MITRE NVD