Microsoft Windows Server 2016

PKU2U authentication using online identities must be prevented

STIG ID: WN16-SO-000340 | SRG: SRG-OS-000480-GPOS-00227 | Severity: Medium | CCI: CCI-000366 | Vulnerability ID: V-225051

Description

PKU2U is a peer-to-peer authentication protocol. This setting prevents online identities from authenticating to domain-joined systems. Authentication will be centrally managed with Windows user accounts.

Check

If the following registry value does not exist or is not configured as specified, this is a finding.Registry Hive: HKEY_LOCAL_MACHINERegistry Path: \SYSTEM\CurrentControlSet\Control\LSA\pku2u\Value Name: AllowOnlineIDType: REG_DWORDValue: 0x00000000 (0)

Fix

Configure the policy value for Computer Configuration >> Windows Settings >> Security Settings >> Local Policies >> Security Options >> "Network security: Allow PKU2U authentication requests to this computer to use online identities" to "Disabled".