Windows Autoit3.exe Created by Uncommon Process (curl.exe/KeyScramblerLogon.exe/etc.)

Alerts on Windows events where Autoit3.exe is created, with the producing process matching curl.exe or other uncommon executables.

FreeReviewedSigma · Medium · v5
Product
windows
Category
file_event
Author
Micah Babinski (SigmaHQ), DRL 1.1
Published
2023-10-15
Updated
2026-07-31
title: Windows Autoit3.exe Created by Uncommon Process (curl.exe/KeyScramblerLogon.exe/etc.)
id: 4ce47442-f3f3-48d1-ab40-5e90fda879a7
status: test
description: This rule flags file creation where Autoit3.exe is created as a target by unusual parent/tool processes such as curl.exe, KeyScramblerLogon.exe, ExtExport.exe, or wmprph.exe. Creating Autoit3.exe via non-standard utilities is a common tactic to stage execution using a scripting/automation binary and evade normal application startup paths. It relies on Windows file event telemetry that records the creating process image and the created target filename, matching on the relevant executable names and ends-with paths.
references:
  - https://github.security.telekom.com/2023/08/darkgate-loader.html
  - https://www.kroll.com/en/insights/publications/cyber/microsoft-teams-used-as-initial-access-for-darkgate-malware
  - https://github.com/pr0xylife/DarkGate/tree/main
  - https://github.com/SigmaHQ/sigma/blob/master/rules-emerging-threats/2023/Malware/DarkGate/file_event_win_malware_darkgate_autoit3_binary_creation.yml
author: Micah Babinski, Huntrule Team
date: 2023-10-15
tags:
  - attack.command-and-control
  - attack.execution
  - attack.t1105
  - attack.t1059
  - detection.emerging-threats
logsource:
  category: file_event
  product: windows
detection:
  selection:
    Image|endswith:
      - \Autoit3.exe
      - \curl.exe
      - \ExtExport.exe
      - \KeyScramblerLogon.exe
      - \wmprph.exe
    TargetFilename|endswith: \Autoit3.exe
  condition: selection
falsepositives:
  - Unknown
level: medium
license: DRL-1.1
related:
  - id: 1a433e1d-03d2-47a6-8063-ece992cf4e73
    type: derived