Potential DLL File Download Via PowerShell Invoke-WebRequest


Description

Detects potential DLL files being downloaded using the PowerShell Invoke-WebRequest or Invoke-RestMethod cmdlets.

Query · sigma

selection:
  CommandLine|contains:
  - 'Invoke-RestMethod '
  - 'Invoke-WebRequest '
  - 'IRM '
  - 'IWR '
  CommandLine|contains|all:
  - http
  - OutFile
  - .dll
condition: selection

Known false positives

  • Unknown
Raw source Potential DLL File Download Via PowerShell Invoke-WebRequest · Sigma
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Published by SigmaHQ/sigma ↗, licensed under Detection Rule License 1.1 ↗. Reproduced here unmodified.
title: Potential DLL File Download Via PowerShell Invoke-WebRequest
id: 0f0450f3-8b47-441e-a31b-15a91dc243e2
status: test
description: Detects potential DLL files being downloaded using the PowerShell Invoke-WebRequest or Invoke-RestMethod cmdlets.
references:
    - https://www.zscaler.com/blogs/security-research/onenote-growing-threat-malware-distribution
author: Florian Roth (Nextron Systems), Hieu Tran
date: 2023-03-13
modified: 2025-07-18
tags:
    - attack.command-and-control
    - attack.execution
    - attack.t1059.001
    - attack.t1105
logsource:
    product: windows
    category: process_creation
detection:
    selection:
        CommandLine|contains:
            - 'Invoke-RestMethod '
            - 'Invoke-WebRequest '
            - 'IRM '
            - 'IWR '
        CommandLine|contains|all:
            - 'http'
            - 'OutFile'
            - '.dll'
    condition: selection
falsepositives:
    - Unknown
level: medium

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