HackTool - SILENTTRINITY Stager Execution

About the rule

Rule Type

Standard

Rule Description

Detects SILENTTRINITY stager use via PE metadata

Severity

Trouble

Rule journey

Attack chain scenario

Initial access → Payload delivery → Stager execution → C2 communication → Post-exploitation → Lateral movement

Impact

• Remote control
• Credential theft
• Stealth access
• Lateral movement

Rule Requirement

Prerequisites

• Using Windows event viewer:

To configure detailed process tracking, log in to a domain controller using domain admin credentials and open the Group Policy Management Console (GPMC). Create a new GPO or modify an existing one linked to the target OU, then navigate to Computer Configuration > Policies > Windows Settings > Security Settings > Advanced Audit Policy Configuration > Audit Policies > Detailed Tracking. Enable both Audit Process Creation and Audit Process Termination with Success logging. For enhanced visibility, also enable "Include command line in process creation events" under Administrative Templates > System > Audit Process Creation, and ensure the appropriate registry key under Microsoft-Windows-Security-Auditing/Operational is created for logging.

• Using Sysmon:

To enable process creation monitoring with Sysmon, first create or download a configuration file that includes the necessary event filters. Install Sysmon using the command sysmon.exe -i [configfile.xml], ensuring that process creation events are properly defined within the <EventFiltering> section. Finally, create the Microsoft-Windows-Sysmon/Operational registry key under the EventLog directory if it does not already exist, to support proper event logging.

Criteria

Detection

Execution Mode

realtime

Log Sources

Windows

MITRE ATT&CK

• Command and Control: Application Layer Protocol (T1071)

Security Standards

Enabling this rule will help you meet the security standard's requirement listed below:

1. NIST SP 800-53: AU-6 - Audit Review, Analysis, and Reporting

Requires organizations to review and analyze audit records for indications of suspicious activities.
Triggering this rule enables the detection of malicious stager execution attempts, supporting audit analysis and timely threat identification.

2. NIST SP 800-53: SI-4 - Information System Monitoring

Mandates monitoring systems to detect attacks and indicators of compromise.
Triggering this rule ensures active monitoring for SILENTTRINITY activity, a known post-exploitation framework, helping identify compromised hosts.

3. NIST SP 800-53: AC-2 - Account Management

Focuses on managing user accounts and detecting unauthorized access or misuse.
Triggering this rule helps flag suspicious remote stager activity that may be tied to compromised or misused accounts.

4. NIST SP 800-61: Incident Response - Detection and Analysis

Guides effective detection and analysis of security incidents.
Triggering this rule provides early visibility into adversary actions, aiding rapid incident detection and analysis during post-exploitation phases.

5. NIST SP 800-171: 3.3.1 - Audit Events

Requires identifying and auditing events that could indicate a security concern.
Triggering this rule highlights the execution of SILENTTRINITY, helping organizations log and respond to potentially malicious activities.

Author

Aleksey Potapov, oscd.community

Future actions

Known False Positives

This rule will be triggered when security teams or red teamers intentionally run SILENTTRINITY for authorized testing or simulation purposes.
It may also fire during lab environments where penetration testing frameworks are being evaluated or demonstrated.

Next Steps

When this rule is triggered, the following measures can be implemented:

1. Identification: Identify if the flagged event is a new incident or part of an existing incident.
2. Analysis: Analyze the impact and extent of the incident to comprehend the severity of the attack using the Incident Workbench.
3. Response: Respond promptly by initiating an automated workflow to interrupt the network connections and cease the malicious process.
4. Containment: Isolate the affected endpoint to prevent lateral movement or further compromise across the network.
5. Investigation: Correlate this event with related logs and threat intelligence to uncover attacker objectives and tactics.

Mitigation