sccmhunter: attacking SCCM related assets in an Active Directory domain

SCCMHunter

SCCMHunter is a post-ex tool built to streamline identifying, profiling, and attacking SCCM related assets in an Active Directory domain. The basic function of the tool is to query LDAP with the find module for potential SCCM-related assets. This is achieved through ACL recon of objects created during the deployment process when extending the AD schema, as well as by performing queries for the keywords “SCCM” or “MECM”. This list of targets is then profiled with the SMB module by checking the remarks for default shares required by assets configured with certain SCCM roles. Additionally, the module checks if the MSSQL service is running and if SMB signing is enforced on the endpoint. All of this helps paint a picture for potential attack paths in the environment. Once profiling is complete, the operator can target abusing client enrollment with the HTTP (@_xpn_) module accounts or use the MSSQL (@_mayyhem) module to grab the necessary syntax for complete site server takeover. If a site server takeover is successful, the admin and pivot modules are available for further information gathering and abuse.

Modules

Find

The find module queries LDAP for default ACLs created during extension of the AD schema during deployment. During installation, under the “System” container, the “System Management” container is created and the site server machine account is granted GenericAll permissions on the container object. Additionally, when configuring a server with the “Management Point” (MP) role in SCCM, the site server publishes this information in the “System Management” container in a mSSMSManagementPoint class object. The MP’s dNSHostName attribute is stored here and is how clients will resolve available management points from AD. The last step is to simply query AD for acronyms related to SCCM or MECM based on administrators tendency use descriptive labels for related users, groups, and systems. All potential site server hostnames are logged for use with the SMB and Http modules.

Here’s an example of the results following running the find module:

SMB

The SMB module takes the results from Find and enumerates the remote hosts SMB shares, SMB signing status, and checks if the server is running MSSQL. During setup of particular roles in SCCM, such as the MP or distribution point (DP) roles, the remarks for default file shares disclose what the particular server’s role is. This is useful due to requirements during deployment for the site server machine account to have local administrator rights for servers configured with the MP, DP, and SQL database roles and are vulnerable to relay attacks if SMB signing is disabled or not required. Through this profiling the operator can streamline the process of identifying this condition. Additionally, the SMB module checks for the existence of the “REMINST” file share found on DPs that indicate the use of PXEBoot. If found, this share is spidered for the presence of media variables files which can be leveraged to potentially obtain, sometimes privileged, domain users credentials as detailed by Christopher Panayi here.

Here’s an example of the results following running the smb module:

HTTP

The HTTP module also takes the results from Find and enumerates the remote hosts for SCCM enrollment web services. If found, the module leverages Adam Chester’s sccmwtf.py script to spoof client enrollment with provided machine account credentials or with the -auto flag attempts to create a new machine. More info on this attack can be found at Adam’s blog here

Here’s an example of the results following running the http module with the -auto flag:

MSSQL

The MSSQL module accepts arguments to provide the correct MSSQL query syntax to abuse the site server takeover attack discovered and detailed by Chris Thompson here. The hex-formatted SID of the user being granted “Full Administrator” permissions is queried and provided in the terminal. Once the first round of queries are complete, the operator is prompted to provide the minted administrator account’s AdminID and the second round of queries printed to the terminal.

Here’s an example of the results following running the mssql module:

Admin

The Admin module is a post site server takeover module intended to query the AdminService API and store recovered data in a local SQLite database. Current information that is stored includes: users, devices, collections, deployments, applications, UserDeviceAffinity. This data can later be queried for useful information such as identifying devices a target user recently logged in or was assigned as a primary user. Note: This module worked in a lab environment. Your mileage may vary depending on the size of the environment it’s used in.

Here are examples of the initial run of recovering data and querying where the target DA user recently signed in.

Pivot

The Pivot module is a post site server takeover module intended to use the CMPivot tool remotely by leveraging the AdminService API. It is currently in a proof of concept state and is missing many useful commands that are still being built and tested. Some examples of how the CMPivot tool is useful is it allows the operator to enumerate a target device or collection and run commands to identify local administrators, running processes, or network configuration.

Here is an example of using the pivot module to query the local administrators group of a machine through the AdminService API:

Show

The show module is intended simply to present the stored CSVs generated during running the find and smb modules. They make for good screenshots 🙂

Here is an example of the show module showing users and groups related to SCCM:

Install

Copyright (c) 2024 Garrett Foster