Microsoft Windows Server 2025
Windows Server 2025 directory service must be configured to terminate LDAP-based network connections to the directory server after five minutes of inactivity
Description
The failure to terminate inactive network connections increases the risk of a successful attack on the directory server. The longer an established session is in progress, the more time an attacker has to hijack the session, implement a means to passively intercept data, or compromise any protections on client access. For example, if an attacker gains control of a client computer, an existing (already authenticated) session with the directory server could allow access to the directory. The lack of confidentiality protection in LDAP-based sessions increases exposure to this vulnerability.
Satisfies: SRG-OS-000163-GPOS-00072, SRG-OS-000279-GPOS-00109
Check
This applies to domain controllers. It is not applicable for other systems.
Open an elevated command prompt (run as administrator).
Enter "ntdsutil".
At the "ntdsutil:" prompt, enter "LDAP policies".
At the "ldap policy:" prompt, enter "connections".
At the "server connections:" prompt, enter "connect to server [host-name]"
(where [host-name] is the computer name of the domain controller).
At the "server connections:" prompt, enter "q".
At the "ldap policy:" prompt, enter "show values".
If the value for MaxConnIdleTime is greater than "300" (5 minutes) or is not specified, this is a finding.
Enter "q" at the "ldap policy:" and "ntdsutil:" prompts to exit.
Alternately, Dsquery can be used to display MaxConnIdleTime:
Open "command prompt (Admin)".
Enter the following command (on a single line).
dsquery * "cn=Default Query Policy,cn=Query-Policies,cn=Directory Service, cn=Windows NT,cn=Services,cn=Configuration,dc=[forest-name]" -attr LDAPAdminLimits
The quotes are required and dc=[forest-name] is the fully qualified LDAP name of the domain being reviewed (e.g., dc=disaost,dc=mil).
If the results do not specify a "MaxConnIdleTime" or it has a value greater than "300" (5 minutes), this is a finding.
Fix
Configure the directory service to terminate LDAP-based network connections to the directory server after 5 minutes of inactivity.
Open an elevated command prompt (run as administrator).
Enter "ntdsutil".
At the "ntdsutil:" prompt, enter "LDAP policies".
At the "ldap policy:" prompt, enter "connections".
At the "server connections:" prompt, enter "connect to server [host-name]" (where [host-name] is the computer name of the domain controller).
At the "server connections:" prompt, enter "q".
At the "ldap policy:" prompt, enter "Set MaxConnIdleTime to 300".
Enter "Commit Changes" to save.
Enter "Show values" to verify changes.
Enter "q" at the "ldap policy:" and "ntdsutil:" prompts to exit.