Summary

This security update resolves a Microsoft Excel remote code execution vulnerability. To learn more, see Microsoft Common Vulnerabilities and Exposures CVE-2021-31939.

Note: To apply this security update, you must have the release version of Microsoft Office Online Server installed on the computer.

Improvements and fixes

This update adds the xmlns attribute to the dependent assemblies in the Web.config file. This change enables Excel Online Web Parts that are created in an earlier version of SharePoint to work in Microsoft SharePoint 2019.

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 Security update deployment information: June 8, 2021 (KB5004128).

Security update replacement information

This security update replaces previously released security update 5001914.

File hash information

File name

SHA256 hash

wacserver2019-kb5001943-fullfile-x64-glb.exe

12C2569B45E2ECD76E411F2C025535958BD416CB6C03972EC9DC8B71F5EDB296

File information

Download the list of files that are included in security update 5001943.

Information about protection and security

Protect yourself online: Windows Security support

Learn how we guard against cyber threats: Microsoft Security

Need more help?

Expand your skills
Explore Training
Get new features first
Join Microsoft Insiders

Was this information helpful?

What affected your experience?

Any additional feedback? (Optional)

Thank you for your feedback!

×