detection.wiki

Detection rules › Sigma

Renamed AutoHotkey.EXE Execution

Status
test
Severity
medium
Log source
category process_creation, product windows
Author
Nasreddine Bencherchali
Source
github.com/SigmaHQ/sigma

Detects execution of a renamed autohotkey.exe binary based on PE metadata fields

MITRE ATT&CK coverage

TacticTechniques
StealthNo specific technique

Telemetry coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule body

title: Renamed AutoHotkey.EXE Execution
id: 0f16d9cf-0616-45c8-8fad-becc11b5a41c
status: test
description: Detects execution of a renamed autohotkey.exe binary based on PE metadata fields
references:
    - https://www.autohotkey.com/download/
    - https://thedfirreport.com/2023/02/06/collect-exfiltrate-sleep-repeat/
author: Nasreddine Bencherchali
date: 2023-02-07
tags:
    - attack.stealth
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        - Product|contains: 'AutoHotkey'
        - Description|contains: 'AutoHotkey'
        - OriginalFileName:
              - 'AutoHotkey.exe'
              - 'AutoHotkey.rc'
    filter:
        - Image|endswith:
              - '\AutoHotkey.exe'
              - '\AutoHotkey32.exe'
              - '\AutoHotkey32_UIA.exe'
              - '\AutoHotkey64.exe'
              - '\AutoHotkey64_UIA.exe'
              - '\AutoHotkeyA32.exe'
              - '\AutoHotkeyA32_UIA.exe'
              - '\AutoHotkeyU32.exe'
              - '\AutoHotkeyU32_UIA.exe'
              - '\AutoHotkeyU64.exe'
              - '\AutoHotkeyU64_UIA.exe'
        - Image|contains: '\AutoHotkey'
    condition: selection and not filter
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: condition

selection and not filter

Stage 1: selection

selection:
    - Product|contains: 'AutoHotkey'
    - Description|contains: 'AutoHotkey'
    - OriginalFileName:
          - 'AutoHotkey.exe'
          - 'AutoHotkey.rc'

Stage 2: not filter

filter:
    - Image|endswith:
          - '\AutoHotkey.exe'
          - '\AutoHotkey32.exe'
          - '\AutoHotkey32_UIA.exe'
          - '\AutoHotkey64.exe'
          - '\AutoHotkey64_UIA.exe'
          - '\AutoHotkeyA32.exe'
          - '\AutoHotkeyA32_UIA.exe'
          - '\AutoHotkeyU32.exe'
          - '\AutoHotkeyU32_UIA.exe'
          - '\AutoHotkeyU64.exe'
          - '\AutoHotkeyU64_UIA.exe'
    - Image|contains: '\AutoHotkey'

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
Imageends_with\AutoHotkey.exeexcludes:Image field:"Image" value:"\AutoHotkey.exe"
Imageends_with\AutoHotkey32.exeexcludes:Image field:"Image" value:"\AutoHotkey32.exe"
Imageends_with\AutoHotkey32_UIA.exeexcludes:Image field:"Image" value:"\AutoHotkey32_UIA.exe"
Imageends_with\AutoHotkey64.exeexcludes:Image field:"Image" value:"\AutoHotkey64.exe"
Imageends_with\AutoHotkey64_UIA.exeexcludes:Image field:"Image" value:"\AutoHotkey64_UIA.exe"
Imageends_with\AutoHotkeyA32.exeexcludes:Image field:"Image" value:"\AutoHotkeyA32.exe"
Imageends_with\AutoHotkeyA32_UIA.exeexcludes:Image field:"Image" value:"\AutoHotkeyA32_UIA.exe"
Imageends_with\AutoHotkeyU32.exeexcludes:Image field:"Image" value:"\AutoHotkeyU32.exe"
Imageends_with\AutoHotkeyU32_UIA.exeexcludes:Image field:"Image" value:"\AutoHotkeyU32_UIA.exe"
Imageends_with\AutoHotkeyU64.exeexcludes:Image field:"Image" value:"\AutoHotkeyU64.exe"
Imageends_with\AutoHotkeyU64_UIA.exeexcludes:Image field:"Image" value:"\AutoHotkeyU64_UIA.exe"
Imagematch\AutoHotkeyexcludes:Image field:"Image" value:"\AutoHotkey"

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
Descriptionmatch
  • AutoHotkey
field:"Description" kind:match value:"AutoHotkey"
OriginalFileNameeq
  • AutoHotkey.exe corpus 3 (elastic 2, sigma 1)
  • AutoHotkey.rc
field:"OriginalFileName" kind:eq
Productmatch
  • AutoHotkey
field:"Product" kind:match value:"AutoHotkey"