Renamed AutoIt Execution — Sigma Rule

Rule metadata and linked tags

Author: Florian Roth (Nextron Systems). Source status: test; severity: high. Source dates: 2023-06-04 / 2024-11-23.

{
  "category": "process_creation",
  "product": "windows"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 981879db98a0e981683f326bcd54e432ba128b86a46561d2434bec5c38303245

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: Renamed AutoIt Execution
id: f4264e47-f522-4c38-a420-04525d5b880f
status: test
description: |
    Detects the execution of a renamed AutoIt2.exe or AutoIt3.exe.
    AutoIt is a scripting language and automation tool for Windows systems. While primarily used for legitimate automation tasks, it can be misused in cyber attacks.
    Attackers can leverage AutoIt to create and distribute malware, including keyloggers, spyware, and botnets. A renamed AutoIt executable is particularly suspicious.
references:
    - https://twitter.com/malmoeb/status/1665463817130725378?s=12&t=C0_T_re0wRP_NfKa27Xw9w
    - https://www.autoitscript.com/site/
author: Florian Roth (Nextron Systems)
date: 2023-06-04
modified: 2024-11-23
tags:
    - attack.stealth
    - attack.t1027
logsource:
    category: process_creation
    product: windows
detection:
    selection_1:
        CommandLine|contains:
            - ' /AutoIt3ExecuteScript'
            - ' /ErrorStdOut'
    selection_2:
        Hashes|contains:
            - 'IMPHASH=FDC554B3A8683918D731685855683DDF'  # AutoIt v2 - doesn't cover all binaries
            - 'IMPHASH=CD30A61B60B3D60CECDB034C8C83C290'  # AutoIt v2 - doesn't cover all binaries
            - 'IMPHASH=F8A00C72F2D667D2EDBB234D0C0AE000'  # AutoIt v3 - doesn't cover all binaries
    selection_3:
        OriginalFileName:
            - 'AutoIt3.exe'
            - 'AutoIt2.exe'
            - 'AutoIt.exe'
    filter_main_legit_name:
        Image|endswith:
            - '\AutoIt.exe'
            - '\AutoIt2.exe'
            - '\AutoIt3_x64.exe'
            - '\AutoIt3.exe'
    condition: 1 of selection_* and not 1 of filter_main_*
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://twitter.com/malmoeb/status/1665463817130725378?s=12&t=C0_T_re0wRP_NfKa27Xw9w
• https://www.autoitscript.com/site/