Windows Server 2019 domain controllers must require LDAP access signing.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-93545	WN19-DC-000320	SV-103631r1_rule		Medium

Description
Unsigned network traffic is susceptible to man-in-the-middle attacks, where an intruder captures packets between the server and the client and modifies them before forwarding them to the client. In the case of an LDAP server, this means that an attacker could cause a client to make decisions based on false records from the LDAP directory. The risk of an attacker pulling this off can be decreased by implementing strong physical security measures to protect the network infrastructure. Furthermore, implementing Internet Protocol security (IPsec) authentication header mode (AH), which performs mutual authentication and packet integrity for Internet Protocol (IP) traffic, can make all types of man-in-the-middle attacks extremely difficult. Satisfies: SRG-OS-000423-GPOS-00187, SRG-OS-000424-GPOS-00188

Description

Unsigned network traffic is susceptible to man-in-the-middle attacks, where an intruder captures packets between the server and the client and modifies them before forwarding them to the client. In the case of an LDAP server, this means that an attacker could cause a client to make decisions based on false records from the LDAP directory. The risk of an attacker pulling this off can be decreased by implementing strong physical security measures to protect the network infrastructure. Furthermore, implementing Internet Protocol security (IPsec) authentication header mode (AH), which performs mutual authentication and packet integrity for Internet Protocol (IP) traffic, can make all types of man-in-the-middle attacks extremely difficult. Satisfies: SRG-OS-000423-GPOS-00187, SRG-OS-000424-GPOS-00188

STIG	Date
Windows Server 2019 Security Technical Implementation Guide	2019-07-09

Details

Check Text ( C-92861r1_chk )
This applies to domain controllers. It is NA for other systems. 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: \SYSTEM\CurrentControlSet\Services\NTDS\Parameters\ Value Name: LDAPServerIntegrity Value Type: REG_DWORD Value: 0x00000002 (2)

Fix Text (F-99789r1_fix)
Configure the policy value for Computer Configuration >> Windows Settings >> Security Settings >> Local Policies >> Security Options >> "Domain controller: LDAP server signing requirements" to "Require signing".