Microsoft has released the KB5073724 update for Windows 10, focusing on security improvements for devices under the Extended Security Updates (ESU) program.
Release Timing and Changes
Available since 2026-01-16, KB5073724 is a security-only update targeting Windows 10 21H2, Enterprise LTSC 2021, and 22H2. It aims to patch vulnerabilities by removing legacy modem drivers such as agrsm64.sys and smserial.sys. Furthermore, it updates the WinSqlite3.dll to address a reported vulnerability.
- Microsoft released KB5073724 on 2026-01-16.
- Applies to Windows 10 21H2, Enterprise LTSC 2021, 22H2 under ESU.
- Includes Secure Boot certificate updates.
- Legacy modem drivers removed.
- WinSqlite3.dll updated for security.
Impact on Business Services
The update influences business users, especially those using Azure Virtual Desktop and Windows 365, without reported issues for private users. The Secure Boot enhancements use device-specific data to ensure a smooth rollout.
Installation and Availability
Installation of KB5073724 is part of the January 2026 Patch Tuesday updates. The update is expected to install automatically, but users may also choose to check Windows Update or download it from Microsoft's update catalog.
This update underscores Microsoft's commitment to enhancing security for its extended support customers, emphasizing controlled rollouts and managing system stability.
