KB5002816: This update fixes the GB18030-2022 China certification issue.

Description of the security update for SharePoint Server 2019: December 9, 2025 (KB5002816)

This security update resolves a Microsoft Outlook Remote Code Execution vulnerability and Microsoft Word Remote Code Execution vulnerability. To learn more about the vulnerabilities, see the following security advisories:

• Microsoft Common Vulnerabilities and Exposures CVE-2025-62562
• ​​​​​​​Microsoft Common Vulnerabilities and Exposures CVE-2025-62559
• ​​​​​​​Microsoft Common Vulnerabilities and Exposures CVE-2025-62558
• Microsoft Common Vulnerabilities and Exposures CVE-2025-62555

Notes:

• This is build 16.0.10417.20075 of the security update package.
• To apply this security update, you must have the release version of Microsoft SharePoint Server 2019 installed on the computer.

Improvements and fixes
This security update contains improvements and fixes for the following nonsecurity issue in SharePoint Server 2019:

• This update fixes the GB18030-2022 China certification issue.