Windows 10 KB5073724: Cumulative Update Overview
Windows 10 KB5073724 is now available, but it is only accessible for users subscribed to ESU (Extended Security Updates). With ESU, security updates will continue through October 2026. However, there will be no major feature changes, as official support for Windows 10 has already ended.
The update, titled "2026-01 Cumulative Update for Windows 10 Version 22H2 for x64-based Systems (KB5073724)," was tested on a Windows 10 ESU system, where it upgraded the OS to Build 19045.6809.
How to Download and Install KB5073724
You can install the update either through the built-in Windows Update interface by navigating to Settings > Updates & Security > Windows Update, or by downloading the offline installer files (.msu) from the Microsoft Update Catalog.
Download Links for Windows 10 KB5073724
Here are the direct download links for Windows 10 KB5073724:
- 64-bit and ARM-64 versions
Note: These installers will not work unless you are subscribed to ESU.
What’s New in Windows 10 Build 19045.6809
Removal of Legacy Modem Drivers
According to the official release notes, Microsoft has removed some specific modem drivers that were previously used for internet connectivity on older PCs. This change is expected to have minimal impact, as 99.99% of users are unlikely to be affected.
Microsoft confirmed that Windows 10 no longer includes the following drivers:
- agrsm.sys (x86) or agrsm64.sys (x64) for Agere (formerly Lucent) and LSI Modem chipsets.
- smserial.sys (x86) or smserl64.sys (x64) for Motorola SM56-era modems.
Devices relying on these drivers may no longer function after installing the update. In testing, modems on older PCs continued to work, but Microsoft advises users to confirm compatibility if they still rely on such hardware.
New Secure Boot Certificates
The update includes new Secure Boot certificates, replacing expired ones. Secure Boot certificates are critical for ensuring that the system only trusts verified boot components, preventing potential vulnerabilities.
On systems such as Windows 10 Enterprise LTSC and ESU, these certificates are automatically updated. While this is particularly important for enterprises, individual users with Windows Update enabled do not need to take additional action.
WinSqlite3.dll Security Fix
Microsoft has also updated a core component, WinSqlite3.dll, to address security vulnerabilities. Previously, some antivirus solutions flagged applications using this file as potentially vulnerable. If security alerts persist, Microsoft recommends:
- Updating all apps from the Microsoft Store.
- Contacting third-party developers if their apps are flagged as using vulnerable sqlite3.dll files.
Are There Any Known Issues in KB5073724?
Microsoft has stated that there are no known issues with the January 2026 Patch Tuesday update for Windows 10. Since Windows 10 is now in the Extended Security Updates phase, new features are being developed exclusively for Windows 11 (25H2 or newer).
If you are still using Windows 10, it is highly recommended to install KB5073724 immediately. This update is part of the Patch Tuesday release and resolves multiple vulnerabilities, including:
- Three zero-day vulnerabilities.
- A total of 112 security issues, including:
- 57 Elevation of Privilege vulnerabilities
- 22 Information Disclosure vulnerabilities
- 5 Spoofing vulnerabilities
In its security bulletin, Microsoft highlighted a fix for an issue in the Desktop Window Manager that could allow unauthorized actors to access local information or read memory addresses. This exploit targeted a remote ALPC port, which has now been addressed.