Windows 11 KB5120998 update released with 35 changes and fixes

The KB5120998 update for Windows 11 versions 25H2 and 24H2 is a preview cumulative update providing 35 quality improvements and new features, including enhanced taskbar positioning and sizing, Start menu customization, and the introduction of an administrator protection feature that hardens security against elevation-of-privilege attacks via profile separation. This feature is off by default and can be enabled via Group Policy or Microsoft Intune. The update does not include security fixes and is optional. It also removes the Windows Management Instrumentation Command-line (WMIC) utility from these versions. Microsoft has noted that some devices may require an additional reboot after installation due to Secure Boot certificate updates.

This update does not address security vulnerabilities and therefore does not directly mitigate any security threats. It introduces quality improvements and new features that may enhance user experience and system management. The administrator protection feature adds a security hardening layer against elevation-of-privilege attacks but is disabled by default and requires manual activation. The removal of WMIC may affect scripts or tools relying on this utility. Some devices may experience an additional reboot during installation due to Secure Boot certificate updates.

No security fixes are included in this optional preview update; therefore, no immediate security mitigation is provided by installing KB5120998. Organizations should test this update in controlled environments before broad deployment. To benefit from the administrator protection feature, it must be manually enabled via Group Policy or Microsoft Intune. Users should monitor official Microsoft Patch Tuesday releases for forthcoming security updates. Be aware of the potential for an additional reboot during installation due to Secure Boot certificate updates.