T1143.md

T1143 - Hidden Window

Description from ATT&CK

Adversaries may implement hidden windows to conceal malicious activity from the plain sight of users. In some cases, windows that would typically be displayed when an application carries out an operation can be hidden. This may be utilized by system administrators to avoid disrupting user work environments when carrying out administrative tasks. Adversaries may abuse operating system functionality to hide otherwise visible windows from users so as not to alert the user to adversary activity on the system.

Windows

There are a variety of features in scripting languages in Windows, such as PowerShell, Jscript, and VBScript to make windows hidden. One example of this is powershell.exe -WindowStyle Hidden. (Citation: PowerShell About 2019)

Mac

The configurations for how applications run on macOS are listed in property list (plist) files. One of the tags in these files can be apple.awt.UIElement, which allows for Java applications to prevent the application's icon from appearing in the Dock. A common use for this is when applications run in the system tray, but don't also want to show up in the Dock. However, adversaries can abuse this feature and hide their running window.(Citation: Antiquated Mac Malware)

Atomic Tests

• Atomic Test #1 - Hidden Window

Atomic Test #1 - Hidden Window

Launch PowerShell with the "-WindowStyle Hidden" argument to conceal PowerShell windows by setting the WindowStyle parameter to hidden.

Supported Platforms: Windows

Inputs:

Name	Description	Type	Default Value
powershell_command	Command to launch calc.exe from a hidden PowerShell Window	String	powershell.exe -WindowStyle hidden calc.exe
powershell_process_name	Name of the created process	string	calc

Attack Commands: Run with powershell!

Start-Process #{powershell_command}