Description of the security update for Office Online Server: October 12, 2021 (KB5002027)

Summary

This security update resolves a Microsoft Excel information disclosure vulnerability, Microsoft Word remote code execution vulnerability, and Microsoft Excel remote code execution vulnerabilities. To learn more about the vulnerabilities, see the following security advisories:

• Microsoft Common Vulnerabilities and Exposures CVE-2021-40472
• Microsoft Common Vulnerabilities and Exposures CVE-2021-40474
• Microsoft Common Vulnerabilities and Exposures CVE-2021-40485
• Microsoft Common Vulnerabilities and Exposures CVE-2021-40486

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

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.

• Download security update 5002027 for the 64-bit version of Office Online Server

More information

Security update deployment information

For deployment information about this update, see Security update deployment information: October 12, 2021 (KB5006940).

Security update replacement information

This security update replaces previously released security update 5001999.

File hash information

File name	SHA256 hash
wacserver2019-kb5002027-fullfile-x64-glb.exe	05622AE83893A226C8C8C3A95480B4F60F6C6FFEA62DBB671F723F64FA1246FC

File information

Download the list of files that are included in security update 5002027.

Information about protection and security

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