CVE-2023-21716
CriticalExploitedMicrosoft Word Remote Code Execution Vulnerability
Published Feb 14, 2023 · Updated Aug 19, 2026
Key Facts
Patch immediately- CVE-2023-21716 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting 365 Apps (Microsoft), Office (Microsoft), Office Long Term Servicing Channel (Microsoft) and 21 more products.
- It is exploited in the wild, listed in Industry KEV feed since Mar 21, 2024. No public exploit code is known.
- EPSS estimates a 85% probability of exploitation in the next 30 days.
- Fixed versions are available, including Microsoft 365 Apps for Enterprise https://aka.ms/OfficeSecurityReleases, Office 16.70.23021201, Microsoft Office 2019 https://aka.ms/OfficeSecurityReleases.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
85%
Higher than 99.7% of all scored CVEs
Exploited in the wild
Yes
1 catalog listing
Public exploit code
None known
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Description
Microsoft Word Remote Code Execution Vulnerability
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| Industry KEV feed | Mar 21, 2024 | n/a | Not reported |
Required action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.
Affected Products
42 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| 365 AppsMicrosoft | See advisory | n/a |
| OfficeMicrosoft | 2019 | 16.70.23021201 |
| Office Long Term Servicing ChannelMicrosoft | 2021 | 16.70.23021201 |
| Office Online ServerMicrosoft | 2016, >= 16.0.1 | 16.0.10395.20001 |
| Office Web AppsMicrosoft | 2013-sp1 | n/a |
Patched Releases
Microsoft 365 Apps for Enterprise
https://aka.ms/OfficeSecurityReleases
Office
16.70.23021201
Microsoft Office 2019
https://aka.ms/OfficeSecurityReleases
Microsoft Office 2019 for Mac
16.70.23021201
Office Long Term Servicing Channel
16.70.23021201
Microsoft Office LTSC 2021
https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC for Mac 2021
16.70.23021201
Office Online Server
16.0.10395.20001
Office Web Apps Server
15.0.5529.1000
Microsoft Office Web Apps Server 2013 Service Pack 1
15.0.5529.1000
Microsoft SharePoint Enterprise Server 2013 Service Pack 1
15.0.5529.1000
Microsoft SharePoint Enterprise Server 2016
16.0.5383.1000
Sharepoint Foundation
15.0.5529.1000
Microsoft SharePoint Foundation 2013 Service Pack 1
15.0.5529.1000
Sharepoint Server
15.0.5529.1000, 16.0.10395.20001, 16.0.15601.20478, 16.0.5383.1000
Microsoft SharePoint Server 2019
16.0.10395.20001
Microsoft SharePoint Server Subscription Edition
16.0.15601.20478
Word
15.0.5529.1000, 16.0.5383.1000
Microsoft Word 2013 Service Pack 1
15.0.5529.1000
Microsoft Word 2016
16.0.5383.1000
SharePoint Server Subscription Edition Language Pack
16.0.15601.20478
Timeline
Publicly disclosed
Feb 14, 2023
Added to Industry KEV feed
Mar 21, 2024
Last updated
Aug 19, 2026
Weakness Type
- CWE-190 Integer Overflow or Wraparound
References
FAQ
Common Questions.
Microsoft Word Remote Code Execution Vulnerability
Affected: 365 Apps (Microsoft); Office (Microsoft) versions 2019; Office Long Term Servicing Channel (Microsoft) versions 2021, among others. The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed since Mar 21, 2024.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
Fixed versions are available, including Microsoft 365 Apps for Enterprise https://aka.ms/OfficeSecurityReleases, Office 16.70.23021201, Microsoft Office 2019 https://aka.ms/OfficeSecurityReleases.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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