Sigma rule: Potential Data Exfiltration Via Audio File

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-2fc2da538353, updated 2023-01-16T00:00:00.000Z.

Rule

Title
Potential Data Exfiltration Via Audio File
Status
test
Level
medium
Author
Nasreddine Bencherchali (Nextron Systems)
Date
2023-01-16
File
rules/windows/powershell/powershell_script/posh_ps_audio_exfiltration.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects potential exfiltration attempt via audio file using PowerShell

Log source

product
windows
category
ps_script
definition
Requirements: Script Block Logging must be enabled

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 (as the rule lists them)

  • Unknown

Tags

  • attack.exfiltration

References

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/powershell/powershell_script/posh_ps_audio_exfiltration.yml

Sources and licences

  • SigmaHQ

    "Potential Data Exfiltration Via Audio File" by Nasreddine Bencherchali (Nextron Systems) (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/powershell/powershell_script/posh_ps_audio_exfiltration.yml.
    Licensed under the Detection Rule License (DRL) 1.1: https://github.com/SigmaHQ/Detection-Rule-License

    Detection Rule License (DRL) 1.1

Cite this page

Dragons Eye Ransomware Tracker, "Sigma rule: Potential Data Exfiltration Via Audio File",
entity page, dataset version ref-2fc2da538353, updated 2023-01-16T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/e4f93c99-396f-47c8-bb0f-201b1fa69034 (accessed 2026-11-03).
Underlying source: SigmaHQ rule e4f93c99-396f-47c8-bb0f-201b1fa69034, commit ccbb0369507f796db0b0ae6854c8a2be471b9d84.

Pages change. The dataset version identifies the data, but no archive of old versions is kept, so this citation cannot be replayed later.