Windows Server 2019 User Account Control must automatically deny standard user requests for elevation.

STIG ID: WN19-SO-000410  |  SRG: SRG-OS-000373-GPOS-00157 |  Severity: medium |  CCI: CCI-002038 |  Vulnerability Id: V-205812 | 

Vulnerability Discussion

User Account Control (UAC) is a security mechanism for limiting the elevation of privileges, including administrative accounts, unless authorized. This setting controls the behavior of elevation when requested by a standard user account.

Satisfies: SRG-OS-000373-GPOS-00157, SRG-OS-000373-GPOS-00156

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: ConsentPromptBehaviorUser

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: Behavior of the elevation prompt for standard users" to "Automatically deny elevation requests".