Windows 11 25H2 – Update KB506881 causes unexpected reboots (no BSOD, silent restart)

Hey everyone,
just wanted to report a serious issue I encountered with Windows 11 25H2 related to the update KB506881.

After installing KB506881 my PC randomly rebooted without warning — no BSOD, no crash report, no error on screen. Only the event log showed “unexpected shutdown / Kernel-Power (Event ID 41)”. Removing the update completely solved the issue. Since uninstalling it, my system has been 100% stable with zero unexpected restarts.

Reproducibility:

Install KB506881 → system performs unexpected shutdowns / reboots
Uninstall KB506881 → issue disappears immediately

System details:

Windows 11 25H2 (Build: 26200)
AMD Ryzen 7800X3D (but issue seems unrelated to hardware)
No BSOD / no memory dump / no bugcheck created
Reliability Monitor only shows “Unexpected Shutdown”

What I already did:

Removed KB506881 manually → issue gone
Blocked the update using PowerShell + scheduled task (hourly) to prevent Windows from reinstalling it

Logs:
Event Viewer → Windows Logs → System
Shows: Kernel-Power 41 (unexpected shutdown) immediately after KB506881 installation.

Has anyone else experienced unexpected reboots after KB506881?

If yes, please comment so Microsoft can see how widespread this is.
I also reported it via Microsoft Feedback Hub.

Thanks!