Toast notifications to the lock screen must be turned off.

STIG ID: WN10-UC-000015  |  SRG: SRG-OS-000095-GPOS-00049 |  Severity: low |  CCI: CCI-000381 |  Vulnerability Id: V-220954 | 

Vulnerability Discussion

Toast notifications that are displayed on the lock screen could display sensitive information to unauthorized personnel. Turning off this feature will limit access to the information to a logged on user.

Check

If the following registry value does not exist or is not configured as specified, this is a finding:

Registry Hive: HKEY_CURRENT_USER
Registry Path: \SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\PushNotifications\

Value Name: NoToastApplicationNotificationOnLockScreen

Value Type: REG_DWORD
Value: 1

Fix

Configure the policy value for User Configuration >> Administrative Templates >> Start Menu and Taskbar >> Notifications >> "Turn off toast notifications on the lock screen" to "Enabled".