HackTool - RedMimicry Winnti Playbook Execution

About the rule

Rule Type

Standard

Rule Description

Detects activity associated with the RedMimicry Winnti playbook, an automated tool used for breach emulation.

Severity

Trouble

Rule journey

Attack chain scenario

Initial access → Playbook deployment → Winnti execution → Credential harvesting → Persistence establishment → Data exfiltration

Impact

• Simulated breach
• Credential exposure
• Detection testing
• Security evaluation

Rule Requirement

Prerequisites

• Using Windows event viewer:

To enable process creation auditing using Windows Event Viewer, log in to a domain controller with domain admin credentials and open the Group Policy Management Console (GPMC). Create or edit a Group Policy Object (GPO) linked to the relevant OU, then navigate to the Advanced Audit Policy Configuration to enable Audit Process Creation and Audit Process Termination, ensuring the Success option is selected. For enhanced tracking, enable the policy to include command-line details in process creation events. Additionally, create the registry key "Microsoft-Windows-Security-Auditing/Operational" to ensure logs are properly recorded.

Alternatively, using Sysmon, download and install it from Microsoft Sysinternals and open a Command Prompt with administrator privileges. Apply a configuration file that monitors process creation (e.g., using <ProcessCreate onmatch="exclude"/>) and install it with sysmon.exe -i [configfile.xml]. To enable logging, create the registry key "Microsoft-Windows-Sysmon/Operational" under the appropriate path if it doesn’t already exist.

• Using Sysmon:

Download and install Sysmon from Microsoft Sysinternals, and run it using a Command Prompt with administrator privileges. Use a configuration file that includes process creation monitoring—such as one with a <ProcessCreate> rule—and install it with the command sysmon.exe -i [configfile.xml]. Finally, create the "Microsoft-Windows-Sysmon/Operational" registry key under HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\EventLog\ if it doesn't already exist to enable proper event logging.

Criteria

Detection

Execution Mode

realtime

Log Sources

Windows

MITRE ATT&CK

• Execution: Native API (T1106)
• Defense Evasion: System Binary Proxy Execution - Rundll32 (T1218.011)
• Execution: Command and Scripting Interpreter - Windows Command Shell (T1059.003)

Security Standards

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

1. NIST SP 800-53: SI-4 – System Monitoring: Requires monitoring of systems to detect unauthorized activity.
   Triggering this rule helps detect breach emulation tools like the Winnti playbook, supporting real-time monitoring of potentially malicious activity.
2. NIST SP 800-53: AU-6 – Audit Review, Analysis, and Reporting: Mandates analysis of audit logs to identify anomalies and threats.
   Triggering this rule provides actionable audit data for detecting advanced emulation behaviors, enabling thorough security analysis.
3. NIST SP 800-53: IR-5 – Incident Monitoring: Focuses on identifying and documenting incidents for timely response.
   Triggering this rule flags breach simulation activity, allowing security teams to investigate and determine if it’s a test or an actual threat.
4. NIST SP 800-137: ISCM – Information Security Continuous Monitoring: Calls for ongoing awareness of information security risks.
   Triggering this rule enhances visibility into simulated attack activity, supporting proactive threat hunting and risk reduction.
5. NIST SP 800-61: Incident Handling Guide: Provides procedures for responding to and managing security incidents.
   Triggering this rule assists in validating incident response processes by detecting emulation scenarios, improving readiness for real attacks.
6. NIST SP 800-171: 3.3.1 – System and Communications Protection: Requires monitoring and alerting on unauthorized activities.
   Triggering this rule helps identify use of breach tools that mimic real adversaries, contributing to better communication protection and defense.

Author

Alexander Rausch

Future actions

Known False Positives

This rule will be triggered when security teams or red teams execute the RedMimicry Winnti playbook during authorized breach simulation exercises. It may also fire during testing or training environments where emulation tools are used for validating detection capabilities.

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 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 system to prevent further execution of the playbook and stop potential emulated attack chains.
5. Validation: Verify whether the detection was part of an authorized red team exercise or breach simulation to avoid unnecessary escalation.

Mitigation