Windows: Emotet .LNK Loader Execution via cmd.exe or PowerShell

Alerts on cmd/powershell-launched commands referencing findstr, a .vbs script, and a .lnk file—indicative of shortcut-triggered loader activity.

FreeReviewedSigma · High · v5
Product
windows
Category
process_creation
Author
@kostastsale (SigmaHQ), DRL 1.1
Published
2022-04-22
Updated
2026-07-31
title: "Windows: Emotet .LNK Loader Execution via cmd.exe or PowerShell"
id: 58578501-c7e7-47a8-bea1-a5a10005e4ab
status: test
description: This rule matches Windows process creation where the parent process is cmd.exe, explorer.exe, or PowerShell.exe, and the spawned process is cmd.exe or PowerShell.exe with command lines containing findstr, .vbs, and .lnk. This behavior is consistent with scripted loader execution following phishing delivery of a shortcut file. It relies on process creation telemetry with executable paths and full command-line arguments.
references:
  - https://web.archive.org/web/20220422215221/https://twitter.com/malware_traffic/status/1517622327000846338
  - https://twitter.com/Cryptolaemus1/status/1517634855940632576
  - https://tria.ge/220422-1pw1pscfdl/
  - https://tria.ge/220422-1nnmyagdf2/
  - https://github.com/SigmaHQ/sigma/blob/master/rules-emerging-threats/2022/Malware/Emotet/proc_creation_win_malware_emotet_loader_execution.yml
author: "@kostastsale, Huntrule Team"
date: 2022-04-22
modified: 2024-08-15
tags:
  - attack.execution
  - attack.t1059.006
  - detection.emerging-threats
logsource:
  category: process_creation
  product: windows
detection:
  selection:
    ParentImage|endswith:
      - \cmd.exe
      - \explorer.exe
      - \powershell.exe
    Image|endswith:
      - \cmd.exe
      - \powershell.exe
    CommandLine|contains|all:
      - findstr
      - .vbs
      - .lnk
  condition: selection
falsepositives:
  - Unlikely
level: high
license: DRL-1.1
related:
  - id: 1f32d820-1d5c-43fe-8fe2-feef0c952eb7
    type: derived