(2014-03-26) Determining Computers Configured With "Trusted For Delegation"

You may need to be able to query AD and find all computer accounts that have been configure with any of the three following delegation options:

1. Trust This User For Delegation To Any Service (Kerberos Only) – A.K.A. "Open Delegation"
2. Trust This User For Delegation To Specified Services Only – Use Any Authenticaton Protocol – A.K.A. "Constrained Delegation"
3. Trust This User For Delegation To Specified Services Only – Use Kerberos Only – A.K.A. "Constrained Delegation"

–

[AD.1] Querying ALL Computers with "Trusted For Delegation To Any Service (Kerberos Only)"

"Trusted For Delegation To Any Service (Kerberos Only)" translates to the "TRUSTED_FOR_DELEGATION" bit on the userAccountControl attribute, which in its turn translates to decimal value "524288".

Import-Module ActiveDirectory

Get-ADComputer -Server "<FQDN of DC>" -SearchBase "<DN of Domain NC>" -LdapFilter "(userAccountControl:1.2.840.113556.1.4.803:=524288)" | %{$_.DistinguishedName}

–

[AD.2a] Querying ALL Computers with "Trusted For Delegation To Specific Services – Any AuthN (At Least One Service Specified)"

"Trusted For Delegation To Specific Services – Any AuthN" translates to the "TRUSTED_TO_AUTHENTICATE_FOR_DELEGATION" bit on the userAccountControl attribute, which in its turn translates to decimal value "16777216".

Import-Module ActiveDirectory 

Get-ADComputer -Server "<FQDN of DC>" -SearchBase "<DN of Domain NC>" -LdapFilter "(&(userAccountControl:1.2.840.113556.1.4.803:=16777216)(msDS-AllowedToDelegateTo=*))" | %{$_.DistinguishedName}

–

[AD.2b] Querying ALL Computers with "Trusted For Delegation To Specific Services – Any AuthN (No Service Specified, Empty List)"

"Trusted For Delegation To Specific Services – Any AuthN" translates to the "TRUSTED_TO_AUTHENTICATE_FOR_DELEGATION" bit on the userAccountControl attribute, which in its turn translates to decimal value "16777216".

Import-Module ActiveDirectory 

Get-ADComputer -Server "<FQDN of DC>" -SearchBase "<DN of Domain NC>" -LdapFilter "(&(userAccountControl:1.2.840.113556.1.4.803:=16777216)(!(msDS-AllowedToDelegateTo=*)))" | %{$_.DistinguishedName}

REMARK: Some systems/applications/appliances may use this scenario to for any protocol and still use open delegation. One example is a Riverbed Steelhead Appliance which is able to optimize network traffic for different protocols. For the WHY I refer to the documentation of the systems/applications/appliances.

–

[AD.3a] Querying ALL Computers with "Trusted For Delegation To Specific Services – Kerberos AuthN (At Least One Service Specified)"

"Trusted For Delegation To Specific Services – Kerberos AuthN" DOES NOT translates to any bit on the userAccountControl attribute.

Import-Module ActiveDirectory 

Get-ADComputer -Server "<FQDN of DC>" -SearchBase "<DN of Domain NC>" -LdapFilter "(&(!(|(userAccountControl:1.2.840.113556.1.4.803:=524288)(userAccountControl:1.2.840.113556.1.4.803:=16777216)))(msDS-AllowedToDelegateTo=*))" | %{$_.DistinguishedName}

–

[AD.3b] Querying ALL Computers with "Trusted For Delegation To Specific Services – Kerberos AuthN (No Service Specified, Empty List)"

It is not possible to query this as "Trusted For Delegation To Specific Services" expects a list of at least one service for which delegation is allowed and in this case it does not translate to any bit on the userAccountControl attribute. Because of that it would return any computer account which basically is a false result!

–

REMARK: I used PowerShell here, but of course you can use the same LDAP filter with any other LDAP Querying tool such as ADFIND. Remember that you may need to amend the LDAP filter to target the correct object type!

–

Cheers,

Jorge

———————————————————————————————

* This posting is provided "AS IS" with no warranties and confers no rights!

* Always evaluate/test yourself before using/implementing this!

* DISCLAIMER: https://jorgequestforknowledge.wordpress.com/disclaimer/

———————————————————————————————

############### Jorge’s Quest For Knowledge #############

######### http://JorgeQuestForKnowledge.wordpress.com/ ########

———————————————————————————————