Remote File Download via PowerShell

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Identifies powershell.exe being used to download an executable file from an untrusted remote destination.

Rule type: eql

Rule indices:

  • winlogbeat-*
  • logs-endpoint.events.*
  • logs-windows.*

Severity: medium

Risk score: 47

Runs every: 5 minutes

Searches indices from: now-9m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

Tags:

  • Elastic
  • Host
  • Windows
  • Threat Detection
  • Command and Control

Version: 2 (version history)

Added (Elastic Stack release): 7.11.0

Last modified (Elastic Stack release): 7.12.0

Rule authors: Elastic

Rule license: Elastic License v2

Rule query

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sequence by host.id, process.entity_id with maxspan=30s [network
where process.name : "powershell.exe" and network.protocol == "dns"
and not dns.question.name : ("localhost", "*.microsoft.com",
"*.azureedge.net", "*.powershellgallery.com", "*.windowsupdate.com",
"metadata.google.internal") and not user.domain : "NT AUTHORITY"]
[file where process.name : "powershell.exe" and event.type ==
"creation" and file.extension : ("exe", "dll", "ps1", "bat") and
not file.name : "__PSScriptPolicy*.ps1"]

Threat mapping

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Framework: MITRE ATT&CKTM

Rule version history

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Version 2 (7.12.0 release)
  • Formatting only