KB4598242 applies to: Windows 10, version 2004, all editions, Windows Server version 2004, Windows 10, version 20H2, all editions, Windows Server, version 20H2, all editions.
- Addresses a security vulnerability issue with HTTPS-based intranet servers. After installing this update, HTTPS-based intranet servers cannot, by default, use a user proxy to detect updates. Scans using these servers will fail if you have not configured a system proxy on the clients. If you must use a user proxy, you must configure the behavior using the policy “Allow user proxy to be used as a fallback if detection using system proxy fails.” To ensure the highest levels of security, also use Windows Server Update Services (WSUS) Transport Layer Security (TLS) certificate pinning on all devices. This change does not affect customers who are using HTTP WSUS servers.
- Addresses a security bypass vulnerability that exists in the way the Printer Remote Procedure Call (RPC) binding handles authentication for the remote Winspool interface. For more information, see KB4599464.
- Security updates to Windows App Platform and Frameworks, Windows Media, Windows Fundamentals, Windows Kernel, Windows Cryptography, Windows Virtualization, Windows Peripherals, and Windows Hybrid Storage Services.
Affected applications include: Microsoft Windows, Microsoft Edge (EdgeHTML-based), Microsoft Office and Microsoft Office Services and Web Apps, Microsoft Windows Codecs Library, Visual Studio, SQL Server, Microsoft Malware Protection Engine, .NET Core, .NET Repository, ASP .NET, and Azure.
You will need to reboot your machine after installing this update. There are a lot of components and some of them are installed at startup in the preboot stage of loading windows.