Invoke-Obfuscation COMPRESS OBFUSCATION - System — Sigma Rule

Rule metadata and linked tags

Author: Timur Zinniatullin, oscd.community. Source status: test; severity: medium. Source dates: 2020-10-18 / 2022-11-29.

{
  "product": "windows",
  "service": "system"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 5e719edcf9c8d79b2b3dfba9e3f61ef063e4fde2de5d1ea371b41b43506d34fd

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Invoke-Obfuscation COMPRESS OBFUSCATION - System
id: 175997c5-803c-4b08-8bb0-70b099f47595
status: test
description: Detects Obfuscated Powershell via COMPRESS OBFUSCATION
references:
    - https://github.com/SigmaHQ/sigma/issues/1009 # (Task 19)
author: Timur Zinniatullin, oscd.community
date: 2020-10-18
modified: 2022-11-29
tags:
    - attack.stealth
    - attack.t1027
    - attack.execution
    - attack.t1059.001
logsource:
    product: windows
    service: system
detection:
    selection:
        Provider_Name: 'Service Control Manager'
        EventID: 7045
        ImagePath|contains|all:
            - 'new-object'
            - 'text.encoding]::ascii'
            - 'readtoend'
        ImagePath|contains:
            - ':system.io.compression.deflatestream'
            - 'system.io.streamreader'
    condition: selection
falsepositives:
    - Unknown
level: medium

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://github.com/SigmaHQ/sigma/issues/1009