CVE-2020-1218 — Microsoft Word Remote Code Execution Vulnerability

Executive Summary

A remote code execution vulnerability exists in Microsoft Word software when it fails to properly handle objects in memory. An attacker who successfully exploited the vulnerability could use a specially crafted file to perform actions in the security context of the current user. For example, the file could then take actions on behalf of the logged-on user with the same permissions as the current user. To exploit the vulnerability, a user must open a specially crafted file with an affected version of Microsoft Word software. 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) that contains a specially crafted file that is designed to exploit the vulnerability. However, an attacker would have no way to force the user to visit the website. Instead, an attacker would have to convince the user to click a link, typically by way of an enticement in an email or Instant Messenger message, and then convince the user to open the specially crafted file. The security update addresses the vulnerability by correcting how Microsoft Word handles files 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 Sep 8 2020

Last Updated Sep 8 2020

Publicly Disclosed No

CISA KEV Not Listed

Known Exploits None Known

EPSS Score 0.03635 — 0.88078 percentile

NVD CVSS 7.8 HIGH — matches MSRC

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C

ATTACK VECTOR

Local

ATTACK COMPLEXITY

Low

PRIVILEGES REQUIRED

None

USER INTERACTION

Required

SCOPE

Unchanged

CONFIDENTIALITY

High

INTEGRITY

High

AVAILABILITY

High

EXPLOIT CODE MATURITY

Proof-of-Concept

REMEDIATION LEVEL

Official Fix

REPORT CONFIDENCE

Confirmed

Temporal Score: 7.0

EPSS Score

0.03635

probability of exploitation in the next 30 days

0.88078 percentile - updated 2026-06-21

View on FIRST.org

Affected Products

20 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 Office 2010 Service Pack 2 (32-bit editions)	`4484533 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Office 2010 Service Pack 2 (64-bit editions)	`4484533 (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	`4484503 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Office Web Apps 2010 Service Pack 2	`4486661 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Office Web Apps 2013 Service Pack 1	`4484518 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft SharePoint Enterprise Server 2013 Service Pack 1	`4484514 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft SharePoint Enterprise Server 2016 4484506 (Security Update) 4484512 (Security Update) Important Remote Code Execution 4484473 4484476 Base: 7.8 Temporal: 7.0 Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C Maybe 4484506 Microsoft SharePoint Server 2010 Service Pack 2	`4484528 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft SharePoint Server 2019 4484505 (Security Update) 4484504 (Security Update) Important Remote Code Execution 4484472 Base: 7.8 Temporal: 7.0 Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C Maybe 4484505 Microsoft Word 2010 Service Pack 2 (32-bit editions)	`4486660 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Word 2010 Service Pack 2 (64-bit editions)	`4486660 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Word 2013 RT Service Pack 1	`4484522 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Word 2013 Service Pack 1 (32-bit editions)	`4484522 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Word 2013 Service Pack 1 (64-bit editions)	`4484522 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Word 2016 (32-bit edition)	`4484510 (Security Update)`	Important	Remote Code Execution	Maybe
Microsoft Word 2016 (64-bit edition)	`4484510 (Security Update)`	Important	Remote Code Execution	Maybe

Patches

11 patches

Article	Type	Restart
`Click to Run`	Security Update	No
`4484533`	Security Update	Maybe
`Release Notes`	Security Update	No
`4484503`	Security Update	Maybe
`4486661`	Security Update	Maybe
`4484518`	Security Update	Maybe
`4484514`	Security Update	Maybe
`4484528`	Security Update	Maybe
`4486660`	Security Update	Maybe
`4484522`	Security Update	Maybe
`4484510`	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

Haifei Li of McAfee IPS Security Research Team

References

MSRC Advisory MITRE NVD