Investigate entities on devices using live response

Applies to:

Live response is a capability that gives your security operations team instantaneous access to a device (also referred to as a machine) using a remote shell connection. This gives you the power to do in-depth investigative work and take immediate response actions to promptly contain identified threats — in real time.

Live response is designed to enhance investigations by enabling your security operations team to collect forensic data, run scripts, send suspicious entities for analysis, remediate threats, and proactively hunt for emerging threats.

With live response, analysts can do all of the following tasks:

  • Run basic and advanced commands to do investigative work on a device.
  • Download files such as malware samples and outcomes of PowerShell scripts.
  • Download files in the background (new!).
  • Upload a PowerShell script or executable to the library and run it on a device from a tenant level.
  • Take or undo remediation actions.

Before you begin

Before you can initiate a session on a device, make sure you fulfill the following requirements:

  • Verify that you're running a supported version of Windows 10.
    Devices must be running one of the following versions of Windows 10:

  • Make sure to install appropriate security updates.

  • Enable live response from the settings page.
    You'll need to enable the live response capability in the Advanced features settings page.

    Note

    Only users with manage security or global admin roles can edit these settings.

  • Ensure that the machine has an Automation Remediation level assigned to it.
    You'll need to enable, at least, the minimum Remediation Level for a given Machine Group. Otherwise you won't be able to establish a Live Response session to a member of that group.

  • Enable live response unsigned script execution (optional).

    Warning

    Allowing the use of unsigned scripts may increase your exposure to threats.

    Running unsigned scripts is not recommended as it can increase your exposure to threats. If you must use them however, you'll need to enable the setting in the Advanced features settings page.

  • Ensure that you have the appropriate permissions.
    Only users who have been provisioned with the appropriate permissions can initiate a session. For more information on role assignments, see Create and manage roles.

    Important

    The option to upload a file to the library is only available to those with the appropriate RBAC permissions. The button is greyed out for users with only delegated permissions.

    Depending on the role that's been granted to you, you can run basic or advanced live response commands. Users permissions are controlled by RBAC custom role.

Live response dashboard overview

When you initiate a live response session on a device, a dashboard opens. The dashboard provides information about the session such as the following:

  • Who created the session
  • When the session started
  • The duration of the session

The dashboard also gives you access to:

  • Disconnect session
  • Upload files to the library
  • Command console
  • Command log

Initiate a live response session on a machine

  1. Log in to Microsoft Defender Security Center.

  2. Navigate to the devices list page and select a machine to investigate. The machines page opens.

  3. Launch the live response session by selecting Initiate live response session. A command console is displayed. Wait while the session connects to the device.

  4. Use the built-in commands to do investigative work. For more information, see Live response commands.

  5. After completing your investigation, select Disconnect session, then select Confirm.

Live response commands

Depending on the role that's been granted to you, you can run basic or advanced live response commands. User permissions are controlled by RBAC custom roles. For more information on role assignments, see Create and manage roles.

Basic commands

The following commands are available for user roles that are granted the ability to run basic live response commands. For more information on role assignments, see Create and manage roles.

Command Description
cd Changes the current directory.
cls Clears the console screen.
connect Initiates a live response session to the device.
connections Shows all the active connections.
dir Shows a list of files and subdirectories in a directory.
download <file_path> & Downloads a file in the background.
drivers Shows all drivers installed on the device.
fg <command ID> Returns a file download to the foreground.
fileinfo Get information about a file.
findfile Locates files by a given name on the device.
help Provides help information for live response commands.
persistence Shows all known persistence methods on the device.
processes Shows all processes running on the device.
registry Shows registry values.
scheduledtasks Shows all scheduled tasks on the device.
services Shows all services on the device.
trace Sets the terminal's logging mode to debug.

Advanced commands

The following commands are available for user roles that are granted the ability to run advanced live response commands. For more information on role assignments see Create and manage roles.

Command Description
analyze Analyses the entity with various incrimination engines to reach a verdict.
getfile Gets a file from the device.
NOTE: This command has a prerequisite command. You can use the -auto command in conjunction with getfile to automatically run the prerequisite command.
run Runs a PowerShell script from the library on the device.
library Lists files that were uploaded to the live response library.
putfile Puts a file from the library to the device. Files are saved in a working folder and are deleted when the device restarts by default.
remediate Remediates an entity on the device. The remediation action will vary depending on the entity type:
- File: delete
- Process: stop, delete image file
- Service: stop, delete image file
- Registry entry: delete
- Scheduled task: remove
- Startup folder item: delete file
NOTE: This command has a prerequisite command. You can use the -auto command in conjunction with remediate to automatically run the prerequisite command.
undo Restores an entity that was remediated.

Use live response commands

The commands that you can use in the console follow similar principles as Windows Commands.

The advanced commands offer a more robust set of actions that allow you to take more powerful actions such as download and upload a file, run scripts on the device, and take remediation actions on an entity.

Get a file from the machine

For scenarios when you'd like get a file from a device you're investigating, you can use the getfile command. This allows you to save the file from the device for further investigation.

Note

The following file size limits apply:

  • getfile limit: 3 GB
  • fileinfo limit: 10 GB
  • library limit: 250 MB

Download a file in the background

To enable your security operations team to continue investigating an impacted device, files can now be downloaded in the background.

  • To download a file in the background, in the live response command console, type download <file_path> &.
  • If you are waiting for a file to be downloaded, you can move it to the background by using Ctrl + Z.
  • To bring a file download to the foreground, in the live response command console, type fg <command_id>.

Here are some examples:

Command What it does
"C:\windows\some_file.exe" & Starts downloading a file named some_file.exe in the background.
fg 1234 Returns a download with command ID 1234 to the foreground.

Put a file in the library

Live response has a library where you can put files into. The library stores files (such as scripts) that can be run in a live response session at the tenant level.

Live response allows PowerShell scripts to run, however you must first put the files into the library before you can run them.

You can have a collection of PowerShell scripts that can run on devices that you initiate live response sessions with.

To upload a file in the library

  1. Click Upload file to library.

  2. Click Browse and select the file.

  3. Provide a brief description.

  4. Specify if you'd like to overwrite a file with the same name.

  5. If you'd like to be know what parameters are needed for the script, select the script parameters check box. In the text field, enter an example and a description.

  6. Click Confirm.

  7. (Optional) To verify that the file was uploaded to the library, run the library command.

Cancel a command

Anytime during a session, you can cancel a command by pressing CTRL + C.

Warning

Using this shortcut will not stop the command in the agent side. It will only cancel the command in the portal. So, changing operations such as "remediate" may continue, while the command is canceled.

Automatically run prerequisite commands

Some commands have prerequisite commands to run. If you don't run the prerequisite command, you'll get an error. For example, running the download command without fileinfo will return an error.

You can use the auto flag to automatically run prerequisite commands, for example:

getfile c:\Users\user\Desktop\work.txt -auto

Run a PowerShell script

Before you can run a PowerShell script, you must first upload it to the library.

After uploading the script to the library, use the run command to run the script.

If you plan to use an unsigned script in the session, you'll need to enable the setting in the Advanced features settings page.

Warning

Allowing the use of unsigned scripts may increase your exposure to threats.

Apply command parameters

  • View the console help to learn about command parameters. To learn about an individual command, run:

    help <command name>

  • When applying parameters to commands, note that parameters are handled based on a fixed order:

    <command name> param1 param2

  • When specifying parameters outside of the fixed order, specify the name of the parameter with a hyphen before providing the value:

    <command name> -param2_name param2

  • When using commands that have prerequisite commands, you can use flags:

    <command name> -type file -id <file path> - auto or remediate file <file path> - auto.

Supported output types

Live response supports table and JSON format output types. For each command, there's a default output behavior. You can modify the output in your preferred output format using the following commands:

  • -output json
  • -output table

Note

Fewer fields are shown in table format due to the limited space. To see more details in the output, you can use the JSON output command so that more details are shown.

Supported output pipes

Live response supports output piping to CLI and file. CLI is the default output behavior. You can pipe the output to a file using the following command: [command] > [filename].txt.

Example:

processes > output.txt

View the command log

Select the Command log tab to see the commands used on the device during a session. Each command is tracked with full details such as:

  • ID
  • Command line
  • Duration
  • Status and input or output side bar

Limitations

  • Live response sessions are limited to 10 live response sessions at a time.
  • Large scale command execution is not supported.
  • A user can only initiate one session at a time.
  • A device can only be in one session at a time.
  • The following file size limits apply:
    • getfile limit: 3 GB
    • fileinfo limit: 10 GB
    • library limit: 250 MB

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