ID | Technique | Tactic |
---|---|---|
T1563.002 | RDP Hijacking | Lateral Movement |
T1563 | Remote Service Session Hijacking | Lateral Movement |
T1543.003 | Windows Service | Persistence |
Detection: Windows Service Create with Tscon
Description
The following analytic detects potential RDP Hijacking attempts by identifying the creation of a Windows service using sc.exe with a binary path that includes tscon.exe. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process creation events and command-line arguments. This activity is significant as it indicates an attacker may be trying to hijack a disconnected RDP session, posing a risk of unauthorized access. If confirmed malicious, the attacker could gain control over an existing user session, leading to potential data theft or further system compromise.
Search
1
2| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.process_name=sc.exe Processes.process="*/dest:rdp-tcp*" by Processes.dest Processes.user Processes.parent_process_name Processes.process_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_service_create_with_tscon_filter`
Data Source
Name | Platform | Sourcetype | Source | Supported App |
---|---|---|---|---|
CrowdStrike ProcessRollup2 | N/A | 'crowdstrike:events:sensor' |
'crowdstrike' |
N/A |
Macros Used
Name | Value |
---|---|
security_content_ctime | convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$) |
windows_service_create_with_tscon_filter | search * |
windows_service_create_with_tscon_filter
is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
Annotations
Default Configuration
This detection is configured by default in Splunk Enterprise Security to run with the following settings:
Setting | Value |
---|---|
Disabled | true |
Cron Schedule | 0 * * * * |
Earliest Time | -70m@m |
Latest Time | -10m@m |
Schedule Window | auto |
Creates Notable | Yes |
Rule Title | %name% |
Rule Description | %description% |
Notable Event Fields | user, dest |
Creates Risk Event | True |
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
False positives may arise in the RDP Hijacking analytic when legitimate administrators access remote sessions for maintenance or troubleshooting purposes. These activities might resemble an attacker''s attempt to hijack a disconnected session, leading to false alarms. To mitigate the risk of false positives and improve the overall security posture, organizations can implement Group Policy to automatically disconnect RDP sessions when they are complete. By enforcing this policy, administrators ensure that disconnected sessions are promptly terminated, reducing the window of opportunity for an attacker to hijack a session. Additionally, organizations can also implement access control mechanisms and monitor the behavior of privileged accounts to further enhance security and reduce the chances of false positives in RDP Hijacking detection.
Associated Analytic Story
Risk Based Analytics (RBA)
Risk Message | Risk Score | Impact | Confidence |
---|---|---|---|
An instance of $parent_process_name$ spawning $process_name$ was identified on endpoint $dest$ by user $user$ attempting to hijack a RDP session. | 64 | 80 | 80 |
References
Detection Testing
Test Type | Status | Dataset | Source | Sourcetype |
---|---|---|---|---|
Validation | ✅ Passing | N/A | N/A | N/A |
Unit | ✅ Passing | Dataset | XmlWinEventLog:Microsoft-Windows-Sysmon/Operational |
xmlwineventlog |
Integration | ✅ Passing | Dataset | XmlWinEventLog:Microsoft-Windows-Sysmon/Operational |
xmlwineventlog |
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