Title

PKU2U authentication using online identities must be prevented. (Cat II impact)

Discussion

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 Content

Analyze the system using the Security Configuration and Analysis snap-in. (See "Performing Analysis with the Security Configuration and Analysis Snap-in" in the STIG Overview document.) Expand the Security Configuration and Analysis tree view. Navigate to Local Policies -> Security Options. If the value for "Network Security: Allow PKU2U authentication requests to this computer to use online identities" is not set to "Disabled", this is a finding. The policy referenced configures the following registry value: Registry Hive: HKEY_LOCAL_MACHINE Subkey: \System\CurrentControlSet\Control\LSA\pku2u\ Value Name: AllowOnlineID Type: REG_DWORD Value: 0

Fix Text

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".

Additional Identifiers

Rule ID: SV-48424r2_rule

Vulnerability ID: V-21953

Group Title: PKU2U Online Identities Authentication

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.