Unauthorized accounts must not have the Impersonate a client after authentication user right.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
WN12-UR-000025	WN12-UR-000025	WN12-UR-000025_rule		Medium

Description
Inappropriate granting of user rights can provide system, administrative, and other high-level capabilities. The "Impersonate a client after authentication" user right allows a program to impersonate another user or account to run on their behalf. An attacker could potentially use this to elevate privileges.

STIG	Date
Microsoft Windows Server 2012 Member Server Security Technical Implementation Guide	2013-07-25

Details

Check Text ( C-WN12-UR-000025_chk )
Verify the effective setting in Local Group Policy Editor. Run "gpedit.msc". Navigate to Local Computer Policy -> Computer Configuration -> Windows Settings -> Security Settings -> Local Policies -> User Rights Assignment. If any accounts or groups other than the following are granted the "Impersonate a client after authentication" user right, this is a finding: Administrators Service Local Service Network Service Severity Override: If an application requires this user right, this can be downgraded to not a finding if the following conditions are met: Vendor documentation must support the requirement for having the user right. The requirement must be documented with the IAO. The application account must meet requirements for application account passwords, such as length (V-36661) and required changes frequency (V-36662).

Check Text ( C-WN12-UR-000025_chk )

Verify the effective setting in Local Group Policy Editor.
Run "gpedit.msc".

Navigate to Local Computer Policy -> Computer Configuration -> Windows Settings -> Security Settings -> Local Policies -> User Rights Assignment.

If any accounts or groups other than the following are granted the "Impersonate a client after authentication" user right, this is a finding:

Administrators
Service
Local Service
Network Service

Severity Override: If an application requires this user right, this can be downgraded to not a finding if the following conditions are met:
Vendor documentation must support the requirement for having the user right.
The requirement must be documented with the IAO.
The application account must meet requirements for application account passwords, such as length (V-36661) and required changes frequency (V-36662).

Fix Text (F-WN12-UR-000025_fix)
Configure the policy value for Computer Configuration -> Windows Settings -> Security Settings -> Local Policies -> User Rights Assignment -> "Impersonate a client after authentication" to only include the following accounts or groups: Administrators Service Local Service Network Service