The Deny log on through Remote Desktop Services user right on member servers must be configured to prevent access from highly privileged domain accounts and local administrator accounts on domain systems, and from unauthenticated access on all systems.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-26486	WN12-UR-000021-MS	SV-51509r2_rule	ECLP-1	Medium

Description
Inappropriate granting of user rights can provide system, administrative, and other high-level capabilities. The "Deny log on through Remote Desktop Services" user right defines the accounts that are prevented from logging on using Remote Desktop Services. In an Active Directory Domain, denying logons to the Enterprise Admins and Domain Admins groups on lower-trust systems helps mitigate the risk of privilege escalation from credential theft attacks which could lead to the compromise of an entire domain. Local administrator accounts on domain-joined systems must also be assigned this right to decrease the risk of lateral movement resulting from credential theft attacks. The Guests group must be assigned this right to prevent unauthenticated access.

Description

Inappropriate granting of user rights can provide system, administrative, and other high-level capabilities. The "Deny log on through Remote Desktop Services" user right defines the accounts that are prevented from logging on using Remote Desktop Services. In an Active Directory Domain, denying logons to the Enterprise Admins and Domain Admins groups on lower-trust systems helps mitigate the risk of privilege escalation from credential theft attacks which could lead to the compromise of an entire domain. Local administrator accounts on domain-joined systems must also be assigned this right to decrease the risk of lateral movement resulting from credential theft attacks. The Guests group must be assigned this right to prevent unauthenticated access.

STIG	Date
Windows Server 2012 / 2012 R2 Member Server Security Technical Implementation Guide	2014-04-02

Details

Check Text ( C-49478r3_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 the following accounts or groups are not defined for the "Deny log on through Remote Desktop Services" user right, this is a finding: Domain Systems Only: Enterprise Admins group Domain Admins group All Local Administrator Accounts: Windows 2012 - use the DenyNetworkAccess group - see V-45589 Windows 2012 R2 - use "Local account" or "Local account and member of Administrators group" All Systems: Guests group Systems dedicated to the management of Active Directory (AD admin platforms, see V-36436 in the Active Directory Domain STIG) are exempt from denying the Enterprise Admins and Domain Admins groups. The related automated benchmarks will verify the group "DenyNetworkAccess" has been assigned this right on domain systems, and that it contains all local accounts that are also members of the Administrators group. Use of other methods may result in false positives requiring manual validation. Do not use the built-in Administrators group. This group must contain the appropriate accounts/groups responsible for administering the system. **Windows 2012 R2 added new built-in security groups for assigning permissions and rights to local accounts. Use these groups instead of creating a group for local administrator accounts to apply to this and other deny rights where required. Assign the group "Local account and member of Administrators group" or the more restrictive "Local account".

Check Text ( C-49478r3_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 the following accounts or groups are not defined for the "Deny log on through Remote Desktop Services" user right, this is a finding:

Domain Systems Only:
Enterprise Admins group
Domain Admins group
*All Local Administrator Accounts:
Windows 2012 - use the DenyNetworkAccess group - see V-45589
**Windows 2012 R2 - use "Local account" or "Local account and member of Administrators group"

All Systems:
Guests group

Systems dedicated to the management of Active Directory (AD admin platforms, see V-36436 in the Active Directory Domain STIG) are exempt from denying the Enterprise Admins and Domain Admins groups.

The related automated benchmarks will verify the group "DenyNetworkAccess" has been assigned this right on domain systems, and that it contains all local accounts that are also members of the Administrators group. Use of other methods may result in false positives requiring manual validation.

*Do not use the built-in Administrators group. This group must contain the appropriate accounts/groups responsible for administering the system.

**Windows 2012 R2 added new built-in security groups for assigning permissions and rights to local accounts. Use these groups instead of creating a group for local administrator accounts to apply to this and other deny rights where required. Assign the group "Local account and member of Administrators group" or the more restrictive "Local account".

Fix Text (F-49699r4_fix)
Configure the policy value for Computer Configuration -> Windows Settings -> Security Settings -> Local Policies -> User Rights Assignment -> "Deny log on through Remote Desktop Services" to include the following: Domain Systems Only: Enterprise Admins group Domain Admins group All Local Administrator Accounts: Windows 2012 - use the DenyNetworkAccess group - see V-45589 Windows 2012 R2 - use "Local account" or "Local account and member of Administrators group" All Systems: Guests group Systems dedicated to the management of Active Directory (AD admin platforms, see V-36436 in the Active Directory Domain STIG) are exempt from denying the Enterprise Admins and Domain Admins groups. The related automated benchmarks will verify the group "DenyNetworkAccess" has been assigned this right on domain systems, and that it contains all local accounts that are also members of the Administrators group. Use of other methods may result in false positives requiring manual validation. Do not use the built-in Administrators group. This group must contain the appropriate accounts/groups responsible for administering the system. **Windows 2012 R2 added new built-in security groups for assigning permissions and rights to local accounts. Use these groups instead of creating a group for local administrator accounts to apply to this and other deny rights where required. Assign the group "Local account and member of Administrators group" or the more restrictive "Local account".

Fix Text (F-49699r4_fix)

Configure the policy value for Computer Configuration -> Windows Settings -> Security Settings -> Local Policies -> User Rights Assignment -> "Deny log on through Remote Desktop Services" to include the following:

Domain Systems Only:
Enterprise Admins group
Domain Admins group
*All Local Administrator Accounts:
Windows 2012 - use the DenyNetworkAccess group - see V-45589
**Windows 2012 R2 - use "Local account" or "Local account and member of Administrators group"

All Systems:
Guests group

Systems dedicated to the management of Active Directory (AD admin platforms, see V-36436 in the Active Directory Domain STIG) are exempt from denying the Enterprise Admins and Domain Admins groups.

The related automated benchmarks will verify the group "DenyNetworkAccess" has been assigned this right on domain systems, and that it contains all local accounts that are also members of the Administrators group. Use of other methods may result in false positives requiring manual validation.

*Do not use the built-in Administrators group. This group must contain the appropriate accounts/groups responsible for administering the system.

**Windows 2012 R2 added new built-in security groups for assigning permissions and rights to local accounts. Use these groups instead of creating a group for local administrator accounts to apply to this and other deny rights where required. Assign the group "Local account and member of Administrators group" or the more restrictive "Local account".