PowerShell Script with Remote Execution Capabilities via WinRM

Elastic Stack Serverless Security

Identifies the use of Cmdlets and methods related to remote execution activities using WinRM. Attackers can abuse WinRM to perform lateral movement using built-in tools.

Rule type: query

Rule indices:

• winlogbeat-*
• logs-windows.powershell*

Severity: low

Risk score: 21

Runs every: 60m

Searches indices from: now-119m (https://www.elastic.co/guide/en/elasticsearch/reference/current/common-options.html#date-math[Date Math format], see also Additional look-back time)

Maximum alerts per execution: 100

References:

• https://attack.mitre.org/techniques/T1021/006/
• https://github.com/cobbr/SharpSploit/blob/master/SharpSploit/LateralMovement/PowerShellRemoting.cs
• https://github.com/BC-SECURITY/Empire/blob/main/empire/server/modules/powershell/lateral_movement/invoke_psremoting.py

Tags:

• Domain: Endpoint
• OS: Windows
• Use Case: Threat Detection
• Tactic: Lateral Movement
• Tactic: Execution
• Data Source: PowerShell Logs
• Rule Type: BBR

Version: 209

Rule authors:

• Elastic

Rule license: Elastic License v2

Setup

The PowerShell Script Block Logging logging policy must be enabled. Steps to implement the logging policy with Advanced Audit Configuration:

Computer Configuration >
Administrative Templates >
Windows PowerShell >
Turn on PowerShell Script Block Logging (Enable)

Steps to implement the logging policy via registry:

reg add "hklm\SOFTWARE\Policies\Microsoft\Windows\PowerShell\ScriptBlockLogging" /v EnableScriptBlockLogging /t REG_DWORD /d 1

event.category:process and host.os.type:windows and
  powershell.file.script_block_text : (
    ("Invoke-WmiMethod" or "Invoke-Command" or "Enter-PSSession") and "ComputerName"
  ) and
  not user.id : "S-1-5-18" and
  not file.directory : (
    "C:\\Program Files\\LogicMonitor\\Agent\\tmp" or
    "C:\\Program Files\\WindowsPowerShell\\Modules\\icinga-powershell-framework\\cache" or
    "C:\\Program Files\\WindowsPowerShell\\Modules\\SmartCardTools\\1.2.2"
  ) and not
  powershell.file.script_block_text : (
    "Export-ModuleMember -Function @('Invoke-Expression''Invoke-Command')" and
    "function Invoke-Command {"
  )

Framework: MITRE ATT&CKTM

• Tactic:

  • Name: Lateral Movement
  • ID: TA0008
  • Reference URL: https://attack.mitre.org/tactics/TA0008/

• Technique:

  • Name: Remote Services
  • ID: T1021
  • Reference URL: https://attack.mitre.org/techniques/T1021/

• Sub-technique:

  • Name: Windows Remote Management
  • ID: T1021.006
  • Reference URL: https://attack.mitre.org/techniques/T1021/006/

• Tactic:

  • Name: Execution
  • ID: TA0002
  • Reference URL: https://attack.mitre.org/tactics/TA0002/

• Technique:

  • Name: Command and Scripting Interpreter
  • ID: T1059
  • Reference URL: https://attack.mitre.org/techniques/T1059/

• Sub-technique:

  • Name: PowerShell
  • ID: T1059.001
  • Reference URL: https://attack.mitre.org/techniques/T1059/001/