HackTool - TruffleSnout Execution

About the rule

Rule Type

Standard

Rule Description

Detects the use of TruffleSnout.exe, an iterative AD discovery toolkit for offensive operators, situational awareness and targeted low noise enumeration.

Severity

Trouble

Rule journey

Attack chain scenario

Initial access → Reconnaissance phase → Sysmon detection → Exploit execution → Privilege escalation → Persistence establishment

Impact

• Privilege escalation
• Logging bypass
• Detection evasion
• System compromise

Rule Requirement

Prerequisites

• Using Windows event viewer:

To enable detailed process auditing, log in to a domain controller with domain admin credentials and launch the Group Policy Management Console (GPMC). Create or edit a GPO linked to the relevant OU, then navigate to Advanced Audit Policy Configuration > Detailed Tracking and enable Audit Process Creation and Audit Process Termination by selecting “Success.” For enhanced visibility, go to Audit Process Creation under Administrative Templates and enable the option to include command line data in events. Finally, ensure the registry key for Microsoft-Windows-Security-Auditing/Operational exists under the EventLog directory to support logging.

• Using Sysmon:

To begin monitoring process creation events, download and install Sysmon from Microsoft Sysinternals, then open a Command Prompt with administrator privileges. Create or obtain a Sysmon configuration file tailored to capture process creation details. Install Sysmon using the command sysmon.exe -i [configfile.xml] to apply the configuration.

Ensure your config file includes relevant event filters—specifically, a <ProcessCreate> rule to track all process creation events. Lastly, confirm that the "Microsoft-Windows-Sysmon/Operational" registry key exists under HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\EventLog\ to enable proper event logging.

Criteria

Detection

Execution Mode

realtime

Log Sources

Active Directory

MITRE ATT&CK

• Discovery: Domain Trust Discovery (T1482)

Security Standards

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

1. NIST SP 800-53 Rev. 5 - SI-4: System Monitoring

Requires the organization to monitor systems to detect unauthorized activity.
Triggering this rule enables proactive detection of exploitation attempts, helping security teams identify and respond to unauthorized or anomalous use of vulnerable drivers like SysmonEOP.

2. NIST SP 800-53 Rev. 5 - AU-6: Audit Review, Analysis, and Reporting

Mandates analysis of audit records to support security incident investigation and response.
Triggering this rule highlights specific process and hash-based indicators that can be correlated during audit reviews to support threat analysis and incident handling.

3. NIST SP 800-53 Rev. 5 - IR-4: Incident Handling

Involves preparation, detection, analysis, containment, recovery, and response to incidents.
Triggering this rule initiates workflows for containment and response, facilitating rapid mitigation of exploits targeting Sysmon vulnerabilities.

4. NIST SP 800-53 Rev. 5 - SI-7: Software, Firmware, and Information Integrity

Ensures that system components are protected against unauthorized changes.
Triggering this rule assists in detecting exploitation of trusted security tools (like Sysmon), thereby maintaining software integrity and exposing tampering attempts.

5. NIST SP 800-171 - 3.14.6: Monitor organizational systems

Organizations must actively monitor systems to identify cybersecurity events.
Triggering this rule supports ongoing monitoring by alerting on suspicious use of privilege escalation tools exploiting known CVEs.

Author

frack113

Future actions

Known False Positives

This rule will be triggered when a security analyst or penetration tester runs WCE in a controlled environment during a red team exercise. It may also be triggered by legitimate testing tools that mimic WCE behavior for credential access validation.

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 affected endpoints to prevent further credential harvesting or lateral movement by the adversary.
5. Eradication: Remove the unauthorized tool and any associated artifacts, and reset compromised credentials to restore a secure state

Mitigation