KB5001403: Servicing stack update for Windows 8.1, Windows RT 8.1, and Windows Server 2012 R2: April 13, 2021
This update applies to the following:
- Windows 8.1 for 32-bit systems
- Windows 8.1 for x64-based systems
- Windows RT 8.1
- Windows Server 2012 R2
- Windows Server 2012 R2 (Server Core installation)
This update makes quality improvements to the servicing stack, which is the component that installs Windows updates. Servicing stack updates (SSU) makes sure that you have a robust and reliable servicing stack so that your devices can receive and install Microsoft updates.
This update also addresses an issue that might prevent the CVE-2020-0689 update from installing. The error message in the CBS.log file is TRUST_E_NOSIGNATURE. To learn more about this security vulnerability, see CVE-2020-0689 | Microsoft Secure Boot Security Feature Bypass Vulnerability.
How to get this update
Method 1: Windows Update
This update is available through Windows Update. It will be downloaded and installed automatically.
Method 2: Microsoft Update Catalog
To get the stand-alone package for this update, go to the Microsoft Update Catalog website.
Method 3: Windows Server Update Services
This update is also available through Windows Server Update Services (WSUS).
There are no prerequisites to apply this update.
You don't have to restart your computer after you apply this update.
Servicing stack updates (SSUs) make changes to how updates are installed and cannot be uninstalled from the device.
Update replacement information
This update replaces the previously released update KB4566425.
Source: KB5001403: Servicing stack update for Windows 8.1, Windows RT 8.1, and Windows Server 2012 R2: April 13, 2021
See also: Security Update Guide - Microsoft Security Response Center
Direct download links for KB5001403 MSU file from Microsoft Update Catalog:
Download KB5001403 MSU for Windows 8.1 32-bit (x86) - 4.7 MB
Download KB5001403 MSU for Windows 8.1 64-bit (x64) - 10.4 MB