IMPORTANT: No additional bug fixes or documentation updates
will be released for this version. For the latest information, see the
current release documentation.
PowerShell Suspicious Script with Audio Capture Capabilities
editPowerShell Suspicious Script with Audio Capture Capabilities
editDetects PowerShell scripts that can record audio, a common feature in popular post-exploitation tooling.
Rule type: query
Rule indices:
- winlogbeat-*
- logs-windows.*
Severity: medium
Risk score: 47
Runs every: 5 minutes
Searches indices from: now-9m (Date Math format, see also Additional look-back time
)
Maximum alerts per execution: 100
References:
Tags:
- Elastic
- Host
- Windows
- Threat Detection
- Collection
Version: 4 (version history)
Added (Elastic Stack release): 7.16.0
Last modified (Elastic Stack release): 8.1.0
Rule authors: Elastic
Rule license: Elastic License v2
Investigation guide
edit## Triage and analysis. ### Investigating PowerShell Suspicious Script with Audio Capture Capabilities PowerShell is one of the main tools used by system administrators for automation, report routines, and other tasks. Attackers can use PowerShell to interact with the Windows API and capture audio from input devices connected to the computer. #### Possible investigation steps: - Examine script content that triggered the detection. - Investigate script execution chain (parent process tree). - Inspect any file or network events from the suspicious PowerShell host process instance. - If the action is suspicious for the user, check for any other activities done by the user in the last 48 hours. ### False Positive Analysis - Verify whether the script content is malicious/harmful. ### Related Rules - PowerShell PSReflect Script - 56f2e9b5-4803-4e44-a0a4-a52dc79d57fe - Potential Process Injection via PowerShell - 2e29e96a-b67c-455a-afe4-de6183431d0d ### Response and Remediation - Immediate response should be taken to validate, investigate, and potentially contain the activity to prevent further post-compromise behavior. ## Config The 'PowerShell Script Block Logging' logging policy must be enabled. Steps to implement the logging policy with 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 ```
Rule query
editevent.category:process and powershell.file.script_block_text : ( Get-MicrophoneAudio or (waveInGetNumDevs and mciSendStringA) )
Threat mapping
editFramework: MITRE ATT&CKTM
-
Tactic:
- Name: Collection
- ID: TA0009
- Reference URL: https://attack.mitre.org/tactics/TA0009/
-
Technique:
- Name: Audio Capture
- ID: T1123
- Reference URL: https://attack.mitre.org/techniques/T1123/
-
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/
Rule version history
edit- Version 4 (8.1.0 release)
-
- Formatting only
- Version 3 (8.0.0 release)
-
-
Updated query, changed from:
event.code:"4104" and powershell.file.script_block_text : ( Get-MicrophoneAudio or (waveInGetNumDevs and mciSendStringA) )
-