Potential Remote Desktop Shadowing Activity

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Potential Remote Desktop Shadowing Activity

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Identifies the modification of the Remote Desktop Protocol (RDP) Shadow registry or the execution of processes indicative of an active RDP shadowing session. An adversary may abuse the RDP Shadowing feature to spy on or control other users active RDP sessions.

Rule type: eql

Rule indices:

  • logs-endpoint.events.process-*
  • logs-endpoint.events.registry-*
  • winlogbeat-*
  • logs-windows.sysmon_operational-*
  • endgame-*

Severity: high

Risk score: 73

Runs every: 5m

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

Maximum alerts per execution: 100

References:

Tags:

  • Domain: Endpoint
  • OS: Windows
  • Use Case: Threat Detection
  • Tactic: Lateral Movement
  • Data Source: Elastic Endgame
  • Data Source: Elastic Defend
  • Data Source: Sysmon

Version: 109

Rule authors:

  • Elastic

Rule license: Elastic License v2

Setup

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Setup

If enabling an EQL rule on a non-elastic-agent index (such as beats) for versions <8.2, events will not define event.ingested and default fallback for EQL rules was not added until version 8.2. Hence for this rule to work effectively, users will need to add a custom ingest pipeline to populate event.ingested to @timestamp. For more details on adding a custom ingest pipeline refer - https://www.elastic.co/guide/en/fleet/current/data-streams-pipeline-tutorial.html

Rule query

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/* Identifies the modification of RDP Shadow registry or
  the execution of processes indicative of active shadow RDP session */

any where host.os.type == "windows" and
(
  (event.category == "registry" and
     registry.path : (
      "HKLM\\Software\\Policies\\Microsoft\\Windows NT\\Terminal Services\\Shadow",
      "\\REGISTRY\\MACHINE\\Software\\Policies\\Microsoft\\Windows NT\\Terminal Services\\Shadow"
    )
  ) or
  (event.category == "process" and event.type == "start" and
     (process.name : ("RdpSaUacHelper.exe", "RdpSaProxy.exe") and process.parent.name : "svchost.exe") or
     (process.pe.original_file_name : "mstsc.exe" and process.args : "/shadow:*")
  )
)

Framework: MITRE ATT&CKTM