Researcher Builds WMI-Based RAT in PowerShell
Security researcher Christopher Truncer released a WMI-based agentless post-exploitation RAT that he developed in PowerShell.
Last year, Truncer released a PowerShell script capable of carrying out different actions via Windows Management Instrumentation (WMI), both on the local and on remote machines. Dubbed WMImplant, the newly released Remote Access Tool (RAT) builds on that script, says Truncer, who is security researcher and Red Teamer at Mandiant.
“WMImplant leverages WMI for the command and control channel, the means for executing actions (gathering data, issuing commands, etc.) on the targeted system, and data storage. It is designed to run both interactively and non-interactively. When using WMImplant interactively, it’s designed to have a menu of commands reminiscent of Meterpreter,” Truncer reveals.
Some of the commands supported by the new tool include reading file contents and downloading files from the remote machine, listing the files and folders for a specific directory, searching for a file on a user-specified drive, and upload a file to the remote machine. It can also be used to list processes and start or kill a specific process.
Additionally, the tool can be used for lateral movement, offering support for running command line commands and getting the output, adding, modifying or removing registry values, enabling or disabling WinRM on the targeted host, running a PowerShell script on a system and receiving output, manipulating scheduled jobs, and creating, modifying, or deleting services.
WMImplant also offers support for data gathering operations (including information on users, targeted system, local and network drives, IP addresses, and installed programs), for logging off users, and for shutting down or restarting targeted systems. It can also be used to determine whether a user is away from the machine and to identify users who have logged into the system.
The security researcher explains that WMImplant uses WMI itself for data storage, and does so by leveraging existing WMI properties. Specifically, it uses the DebugFilePath property, which the researcher discovered that could store more than 250 megabytes of data. WMImplant’s command and control communications methodology is also shaped by this, the researcher says.
The RAT was designed for both interactive and non-interactive use, but the researcher says that the easiest way to use WMImplant is interactively, although that is not always possible. Unlike RATs such as Meterpreter or Cobalt Strike’s Beacon, which can load and execute PowerShell scripts, but require non-interactive use only, WMImplant has a built-in command-line generating feature that changes that.
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