Detection: Windows Remote Service Rdpwinst Tool Execution

Description

The following analytic detects the execution of the RDPWInst.exe tool, which is an RDP wrapper library used to enable remote desktop host support and concurrent RDP sessions. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names, original file names, and specific command-line arguments. This activity is significant because adversaries can abuse this tool to establish unauthorized RDP connections, facilitating remote access and potential lateral movement within the network. If confirmed malicious, this could lead to unauthorized access, data exfiltration, and further compromise of the targeted host.

Search

1
2| tstats `security_content_summariesonly` values(Processes.process) as process min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where (Processes.process_name="RDPWInst.exe" OR Processes.original_file_name="RDPWInst.exe") AND Processes.process IN ("* -i*", "* -s*", "* -o*", "* -w*", "* -r*") by Processes.dest Processes.user Processes.parent_process Processes.process_name Processes.original_file_name Processes.process Processes.process_id Processes.parent_process_id 
3| `drop_dm_object_name(Processes)` 
4| `security_content_ctime(firstTime)` 
5| `security_content_ctime(lastTime)` 
6| `windows_remote_service_rdpwinst_tool_execution_filter`

Data Source

Name	Platform	Sourcetype	Source
CrowdStrike ProcessRollup2	N/A	'crowdstrike:events:sensor'	'crowdstrike'
Sysmon EventID 1	Windows	'xmlwineventlog'	'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational'
Windows Event Log Security 4688	Windows	'xmlwineventlog'	'XmlWinEventLog:Security'

Macros Used

Annotations

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Implementation

The detection is based on data that originates from Endpoint Detection and Response (EDR) agents. These agents are designed to provide security-related telemetry from the endpoints where the agent is installed. To implement this search, you must ingest logs that contain the process GUID, process name, and parent process. Additionally, you must ingest complete command-line executions. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the EDR product. The logs must also be mapped to the Processes node of the Endpoint data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process.

Known False Positives

This tool was designed for home usage and not commonly seen in production environment. Filter as needed.

Associated Analytic Story

• Azorult

Risk Based Analytics (RBA)

References

• https://app.any.run/tasks/a6f2ffe2-e6e2-4396-ae2e-04ea0143f2d8/

Detection Testing

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

Source: GitHub | Version: 3