September 8, 2020—KB4577021 (OS Build 15063.2500)

Applies to: Windows 10, version 1703, all editions

Highlights


  • Updates time zone information for the Yukon, Canada.
  • Updates to improve security when using Microsoft Office products.
  • Updates to improve security when using input devices such as a mouse, keyboard, or pen.
  • Updates to improve security in the Microsoft Store.
  • Updates to improve security when Windows performs basic operations.
  • Updates for storing and managing files.

Improvements and fixes


This security update includes quality improvements. Key changes include:

  • Addresses a security vulnerability issue with user proxies and HTTP-based intranet servers. After installing this update, HTTP-based intranet servers cannot leverage a user proxy by default to detect updates. Scans using these servers will fail if the clients do not have a configured system proxy. If you must leverage a user proxy, you must configure the behavior using the Windows Update policy “Allow user proxy to be used as a fallback if detection using system proxy fails.” This change does not affect customers who secure their Windows Server Update Services (WSUS) servers with the Transport Layer Security (TLS) or Secure Sockets Layer (SSL) protocols. For more information, see Improving security for devices receiving updates via WSUS.
  • Updates time zone information for the Yukon, Canada.
  • Security updates to Windows App Platform and Frameworks, Microsoft Graphics Component, Windows Input and Composition, Windows Media, Windows Shell, the Microsoft Store, Windows Cloud Infrastructure, Windows Fundamentals, Windows Kernel, Windows Virtualization, Windows Storage and Filesystems, the Microsoft Scripting Engine, and the Microsoft JET Database Engine.

If you installed earlier updates, only the new fixes contained in this package will be downloaded and installed on your device.

For more information about the resolved security vulnerabilities, please refer to the Security Update Guide.

Known issues in this update


Microsoft is currently not aware of any issues with this update.

How to get this update


Before installing this update

Microsoft strongly recommends you install the latest servicing stack update (SSU) for your operating system before installing the latest cumulative update (LCU). SSUs improve the reliability of the update process to mitigate potential issues while installing the LCU and applying Microsoft security fixes. For general information about SSUs, see Servicing stack updates and Servicing Stack Updates (SSU): Frequently Asked Questions.

If you are using Windows Update, the latest SSU (KB4565551) will be offered to you automatically. To get the standalone package for the latest SSU, search for it in the Microsoft Update Catalog

Install this update

Release Channel Available Next Step
Windows Update and Microsoft Update Yes None. This update will be downloaded and installed automatically from Windows Update.
Microsoft Update Catalog Yes To get the standalone package for this update, go to the Microsoft Update Catalog website.
Windows Server Update Services (WSUS) Yes

This update will automatically sync with WSUS if you configure Products and Classifications as follows:

Product: Windows 10

Classification: Security Updates

 

File information

For a list of the files that are provided in this update, download the file information for cumulative update 4577021