Suspicious PowerShell Download - PoshModule (via ps_module)

title: Suspicious PowerShell Download - PoshModule (via ps_module)
id: 802c96a7-72b7-5083-ac7e-d79f987cdd4e
status: stable
description: This rule detects anomalous PowerShell download command
references:
    - https://attack.mitre.org/techniques/T1059/001/
    - https://learn.microsoft.com/en-us/dotnet/api/system.net.webclient.downloadfile?view=net-8.0
    - https://learn.microsoft.com/en-us/dotnet/api/system.net.webclient.downloadstring?view=net-8.0
author: Huntrule Team
date: 2026-06-18
tags:
    - attack.execution
    - attack.t1059.001
logsource:
    product: windows
    category: ps_module
    definition: 0ad03ef1-f21b-4a79-8ce8-e6900c54b65b
detection:
    selection_webclient_:
        ContextInfo|contains: 'System.Net.WebClient'
    selection_function:
        ContextInfo|contains:
            - '.DownloadFile('
            - '.DownloadString('
    condition: all of selection_*
falsepositives:
    - Unknown
level: medium