Potential Remote Desktop Shadowing Activity

Elastic Stack Serverless Security

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.*
• winlogbeat-*
• logs-windows.*

Severity: high

Risk score: 73

Runs every: 5m

Searches indices from: now-9m (https://www.elastic.co/guide/en/elasticsearch/reference/current/common-options.html#date-math[Date Math format], see also Additional look-back time)

Maximum alerts per execution: 100

References:

• https://bitsadm.in/blog/spying-on-users-using-rdp-shadowing
• https://swarm.ptsecurity.com/remote-desktop-services-shadowing/

Tags:

• Elastic
• Host
• Windows
• Threat Detection
• Lateral Movement

Version: 102

Rule authors:

• Elastic

Rule license: Elastic License v2

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

any where
  (event.category == "registry" and
     registry.path : "HKLM\\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

• Tactic:

  • Name: Lateral Movement
  • ID: TA0008
  • Reference URL: https://attack.mitre.org/tactics/TA0008/

• Technique:

  • Name: Remote Services
  • ID: T1021
  • Reference URL: https://attack.mitre.org/techniques/T1021/