Summary
This security update resolves a Microsoft Office remote code execution vulnerability. To learn more about the vulnerability, see the following security advisories:
- Microsoft Common Vulnerabilities and Exposures CVE-2026-81952
- Microsoft Common Vulnerabilities and Exposures CVE-2026-81955
Note
To apply this security update, you must have the release version of Microsoft Office 2016 installed on the computer.
Be aware that the update in the Microsoft Download Center applies to the Microsoft Installer (.msi)-based edition of Office 2016. It doesn't apply to the Office 2016 Click-to-Run editions, such as Microsoft Office 365 Home. (See What version of Office am I using?)
How to get and install the update
Method 1: Microsoft Update
This update is available from Microsoft Update. When you turn on automatic updating, this update will be downloaded and installed automatically. For more information about how to get security updates automatically, see Windows Update: FAQ.
Method 2: Microsoft Update Catalog
To get the standalone package for this update, go to the Microsoft Update Catalog website.
Method 3: Microsoft Download Center
You can get the standalone update package through the Microsoft Download Center. Follow the installation instructions on the download page to install the update.
More information
Security update deployment information
For deployment information about this update, see Deployments - Security Update Guide.
Security update replacement information
This security update replaces previously released security update 5002795.
File hash information
| File name | SHA256 hash |
|---|---|
| msodll99l2016-kb5002918-fullfile-x86-glb.exe | B79A7C8CF54C69DD3C8B5ADE1543EB272F4AB3CE02FE09610DF10829808EA3B4 |
| msodll99l2016-kb5002918-fullfile-x64-glb.exe | B416882BF9227B5057B58BC2A1E35C6C69DF6B1BCEBAE9BB3693EA6E4725A6C1 |
File information
The English (United States) version of this software update installs files that have the attributes that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). The dates and times for these files on your local computer are displayed in your local time together with your current daylight saving time (DST) bias. Additionally, the dates and times may change when you perform certain operations on the files.
For all supported x86-based versions of Office 2016
| File name | File version | File size | Date | Time |
|---|---|---|---|---|
| Mso99lres.dll | 16.0.4684.1000 | 95,01,424 | 01-09-2026 | 02:14 |
| Mso99lwin32client.dll.x64 | 16.0.5569.1000 | 81,85,696 | 01-09-2026 | 02:16 |
| Mso99lwin32client.dll.x86 | 16.0.5569.1000 | 58,78,552 | 01-09-2026 | 02:14 |
For all supported x64-based versions of Office 2016
| File name | File version | File size | Date | Time |
|---|---|---|---|---|
| Mso99lres.dll | 16.0.4666.1000 | 95,01,416 | 01-09-2026 | 02:11 |
| Mso99lres.dll.x86 | 16.0.5569.1000 | 95,01,424 | 01-09-2026 | 02:17 |
| Mso99lwin32client.dll.x64 | 16.0.5569.1000 | 81,85,696 | 01-09-2026 | 02:12 |
| Mso99lwin32client.dll.x86 | 16.0.5569.1000 | 58,78,552 | 01-09-2026 | 02:17 |
Information about protection and security
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