Windows Server 2019 UIAccess applications must not be allowed to prompt for elevation without using the secure desktop.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-205716	SRG-OS-000134-GPOS-00068	WN19-SO-000390	SV-205716r958518_rule	2025-02-25	3

Description
User Account Control (UAC) is a security mechanism for limiting the elevation of privileges, including administrative accounts, unless authorized. This setting prevents User Interface Accessibility programs from disabling the secure desktop for elevation prompts.

ℹ️ Check
UAC requirements are NA for Server Core installations (this is the default installation option for Windows Server 2019 versus Server with Desktop Experience). If the following registry value does not exist or is not configured as specified, this is a finding: Registry Hive: HKEY_LOCAL_MACHINE Registry Path: \SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\ Value Name: EnableUIADesktopToggle Value Type: REG_DWORD Value: 0x00000000 (0)

ℹ️ Check

UAC requirements are NA for Server Core installations (this is the default installation option for Windows Server 2019 versus Server with Desktop Experience). If the following registry value does not exist or is not configured as specified, this is a finding: Registry Hive: HKEY_LOCAL_MACHINE Registry Path: \SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\ Value Name: EnableUIADesktopToggle Value Type: REG_DWORD Value: 0x00000000 (0)

✔️ Fix
Configure the policy value for Computer Configuration >> Windows Settings >> Security Settings >> Local Policies >> Security Options >> "User Account Control: Allow UIAccess applications to prompt for elevation without using the secure desktop" to "Disabled".