What Does Windows 11 Update KB5073455 Include?
KB5073455 is a cumulative security update released on January 13, 2026 for Windows 11 version 23H2. After installation, the system build updates to 22631.6491.
This update focuses mainly on security fixes, system stability, and background improvements, rather than visible new features.
Key Changes and Fixes
Security updates
- Includes all January 2026 Patch Tuesday security fixes.
- Addresses multiple vulnerabilities across core Windows components to keep systems protected.
Application stability improvements
- Fixes an issue where typing text could cause apps like Outlook, Teams, Excel, Edge, or Chrome to stop responding or crash unexpectedly.
Remote Desktop reliability
- Resolves a bug that could cause Remote Desktop sessions to disconnect or force an unexpected system restart.
Legacy modem driver removal
- Microsoft has permanently removed several very old modem drivers.
- This only affects systems using legacy dial-up or outdated modem hardware. Most modern PCs will not notice any change.
Secure Boot certificate updates
- Begins a gradual rollout of updated Secure Boot certificates.
- The rollout uses device compatibility checks to avoid boot issues on unsupported hardware.
Core system component update
- Updates the built-in Windows SQLite component (
WinSqlite3.dll) to address compatibility and security detection concerns.
Servicing Stack Update included
- Includes an updated servicing stack, which improves how Windows installs future updates and reduces update failures.
Who Should Install It?
- Strongly recommended for all Windows 11 23H2 users due to security fixes.
- Especially important for users relying on Remote Desktop or enterprise environments.
Who Might Want to Be Cautious?
- Users with very old modem hardware.
- Some early reports suggest shutdown or restart behavior issues on specific systems with advanced Secure Launch settings enabled (not yet officially listed as a known issue).
⚠️ Be cautious before updating (Read this first): [ Windows 11 Restarting Instead of Shutting Down After Update (KB5073455) ]
KB5073455 is a maintenance and security-focused update. It doesn’t change how Windows looks, but it improves reliability, security, and update stability behind the scenes — which is exactly what a Patch Tuesday update is meant to do.
