Detection rules › Sigma
Potential Keylogger Activity
Detects PowerShell scripts that contains reference to keystroke capturing functions
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Credential Access | |
| Collection |
Telemetry coverage
| Provider | Record / event type |
|---|---|
| PowerShell | Event ID 4104: Creating Scriptblock text (MessageNumber of MessageTotal). |
Rule body
title: Potential Keylogger Activity
id: 965e2db9-eddb-4cf6-a986-7a967df651e4
status: test
description: Detects PowerShell scripts that contains reference to keystroke capturing functions
references:
- https://twitter.com/ScumBots/status/1610626724257046529
- https://www.virustotal.com/gui/file/d4486b63512755316625230e0c9c81655093be93876e0d80732e7eeaf7d83476/content
- https://www.virustotal.com/gui/file/720a7ee9f2178c70501d7e3f4bcc28a4f456e200486dbd401b25af6da3b4da62/content
- https://learn.microsoft.com/en-us/dotnet/api/system.windows.input.keyboard.iskeydown?view=windowsdesktop-7.0
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-01-04
tags:
- attack.collection
- attack.credential-access
- attack.t1056.001
logsource:
product: windows
category: ps_script
definition: 'Requirements: Script Block Logging must be enabled'
detection:
selection:
ScriptBlockText|contains: '[Windows.Input.Keyboard]::IsKeyDown([System.Windows.Input.Key]::'
condition: selection
falsepositives:
- Unknown
level: medium
Stages and Predicates
Stage 0: condition
selectionStage 1: selection
selection:
ScriptBlockText|contains: '[Windows.Input.Keyboard]::IsKeyDown([System.Windows.Input.Key]::'
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
ScriptBlockText | match |
| field:"ScriptBlockText" kind:match value:"[Windows.Input.Keyboard]::IsKeyDown([System.Windows.Input.Key]::" |