PowerShell Download Pattern — Sigma Rule

Rule metadata and linked tags

Author: Florian Roth (Nextron Systems), oscd.community, Jonhnathan Ribeiro. Source status: test; severity: medium. Source dates: 2019-01-16 / 2025-10-20.

{
  "category": "process_creation",
  "product": "windows"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 58cdce2b40b1312aebfffdc7fcece5f4a71f9d7e9569a9fa7f5dc9ecdb6d1aa3

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: PowerShell Download Pattern
id: 3b6ab547-8ec2-4991-b9d2-2b06702a48d7
related:
    - id: e6c54d94-498c-4562-a37c-b469d8e9a275
      type: derived
    - id: 8f70ac5f-1f6f-4f8e-b454-db19561216c5
      type: obsolete
status: test
description: Detects a Powershell process that contains download commands in its command line string
references:
    - https://blog.redteam.pl/2020/06/black-kingdom-ransomware.html
    - https://lab52.io/blog/winter-vivern-all-summer/
    - https://hatching.io/blog/powershell-analysis/
author: Florian Roth (Nextron Systems), oscd.community, Jonhnathan Ribeiro
date: 2019-01-16
modified: 2025-10-20
tags:
    - attack.execution
    - attack.t1059.001
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith:
              - '\powershell_ise.exe'
              - '\powershell.exe'
              - '\pwsh.exe'
        - OriginalFileName:
              - 'PowerShell_ISE.EXE'
              - 'PowerShell.EXE'
              - 'pwsh.dll'
    selection_cli:
        CommandLine|contains|all:
            - 'new-object'
            - 'net.webclient).'
            - 'download'
        CommandLine|contains:
            - 'string('
            - 'file('
    condition: all of selection_*
falsepositives:
    - Unknown
level: medium

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://blog.redteam.pl/2020/06/black-kingdom-ransomware.html
• https://lab52.io/blog/winter-vivern-all-summer/
• https://hatching.io/blog/powershell-analysis/