LogonUI is hanging with our custom credential provider after installing KB5068861

Hello All,

We have a custom Windows Credential Provider that supports both Network Logon and Workstation Logon. It was working correctly until the installation of the KB5068861 Windows update. After installing this update, LogonUI starts hanging.

Below are the steps to reproduce the issue:

1. LogonUI loads and our Credential Provider displays the username/password input controls.

2. The user enters the username and password but leaves the system idle for about 30–60 seconds without clicking the Submit/OK button.

3. After this idle period, LogonUI/Winlogon hangs. The UI stops responding, and the user cannot click anywhere.

4. The only recovery option is to forcefully reboot the system.

5. If we uninstall KB5068861, everything works normally again.

Request you to share the steps or guidelines on how we can troubleshoot this issue.

Thank you.