This security update resolves a cross-site-scripting (XSS) vulnerability that exists if Microsoft SharePoint Server does not correctly sanitize a specially crafted web request to an affected SharePoint server. This update also resolves a remote code execution vulnerability that exists in Microsoft SharePoint if the software does not check the source markup of an application package. To learn more about the vulnerabilities, see the following security advisories:
Note To apply this security update, you must have the release version of Microsoft SharePoint Server 2019 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.
Security update deployment information
For deployment information about this update, see security update deployment information: April 14, 2020.
Security update replacement information
This security update replaces previously released update 4484271.
File hash information
Information about protection and security
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