Detectionmediumtest
Potential Data Exfiltration Via Audio File
Detects potential exfiltration attempt via audio file using PowerShell
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Launch
Nasreddine Bencherchali (Nextron Systems)Created Mon Jan 16e4f93c99-396f-47c8-bb0f-201b1fa69034windows
Log Source
WindowsPowerShell Script
ProductWindows← raw: windows
CategoryPowerShell Script← raw: ps_script
Definition
Requirements: Script Block Logging must be enabled
Detection Logic
Detection Logic2 selectors
detection:
selection_main:
ScriptBlockText|contains|all:
- '[System.Math]::'
- '[IO.FileMode]::'
- 'BinaryWriter'
selection_header_wav:
ScriptBlockText|contains|all:
# Byte chunks from the WAV header used in the example POC
# You can extend this for different audio formats by adding different selections
- '0x52'
- '0x49'
- '0x46'
- '0x57'
- '0x41'
- '0x56'
- '0x45'
- '0xAC'
condition: selection_main and 1 of selection_header_*False Positives
Unknown
False positive likelihood has not been assessed. Additional context may be needed during triage.
References
MITRE ATT&CK
Tactics
Rule Metadata
Rule ID
e4f93c99-396f-47c8-bb0f-201b1fa69034
Status
test
Level
medium
Type
Detection
Created
Mon Jan 16
Path
rules/windows/powershell/powershell_script/posh_ps_audio_exfiltration.yml
Raw Tags
attack.exfiltration