Analyzing Nation-State Malware with Hybrid Analysis: A Step-by-Step Guide

Cybersecurity professionals often face the challenge of identifying and understanding advanced malware used in nation-state cyberattacks. This article from a recent Tech Talk Tuesday featuring Dan Gunter, explores an efficient method to analyze such malware, specifically focusing on BlackEnergy, a modular trojan used in cyber operations against Ukraine and Poland. Using Hybrid Analysis, a free malware sandboxing tool, we can extract critical attack techniques and understand how adversaries operate.

Understanding the BlackEnergy Malware

BlackEnergy is a well-known piece of malware that has been widely used in cyberattacks targeting government entities, media, and critical infrastructure. It typically spreads through:

• Malicious Office Macros: Attackers embed macros in Word, Excel, or PowerPoint files to execute the payload when opened.

• Exploiting Microsoft Office Vulnerabilities: Known exploits like CVE-2014-1761 have been used to deliver BlackEnergy.

Once executed, BlackEnergy functions as a modular trojan, meaning it can download additional payloads, including:

• Keyloggers – To capture user keystrokes.

• Screenshot Capture – To monitor user activity.

• Remote Desktop Access – Allowing attackers full control over an infected system.

Given these capabilities, analyzing BlackEnergy is crucial for understanding how such malware operates and how to defend against it.

Step 1: Obtaining and Uploading the Malware Sample

To analyze BlackEnergy (or any malware sample), security researchers use publicly available repositories like:

• Hybrid Analysis (free version) – A sandboxed malware analysis platform.

• VirusTotal (paid version) – A malware intelligence service.

• Other sources – GitHub and cybersecurity research sites may also have samples.

Uploading a sample to Hybrid Analysis allows researchers to examine both static and dynamic behavior in a controlled environment.

Step 2: Performing Static and Dynamic Analysis

Hybrid Analysis provides two key methods of malware investigation:

1. Static Analysis – Examines the file structure without executing the malware. This includes:

   • Identifying the file type (e.g., an Excel spreadsheet with embedded scripts).

   • Extracting embedded scripts and commands within the document.

   • Analyzing imported functions and dependencies.

2. Dynamic Analysis – Executes the malware in a virtual environment to observe its behavior. This includes:

   • Screenshots of the malware’s execution (e.g., opening an Office document and running a script).

   • Process tree analysis – Showing parent-child relationships of running processes.

   • Dropped files analysis – Identifying additional payloads deployed by the malware.

However, it’s important to note that some malware is designed to detect sandbox environments and may refuse to execute properly.

Step 3: Mapping to MITRE ATT&CK Techniques

One of the most powerful features of Hybrid Analysis is its ability to map observed behaviors to the MITRE ATT&CK framework. This provides:

• A clear breakdown of techniques used by the malware.

• Confidence levels (Informative, Suspicious, Malicious) assigned to different findings.

• Process command-line details, helping researchers understand how commands were executed.

For example, in the case of BlackEnergy, the tool identified:

• T1059.003 (Windows Command Shell Execution): The malware executed commands via cmd.exe.

• T1204.002 (Malicious Office Documents): The sample contained an embedded macro that ran upon opening the document.

• T1036 (Masquerading): The malware disguised itself as a legitimate document.

These insights allow security teams to pivot their investigation by searching logs for similar command-line executions in their networks.

Step 4: Reanalyzing Older Reports

Malware evolves over time, and previously analyzed samples may not include newer detection techniques. Hybrid Analysis allows researchers to:

• Reanalyze old samples using updated detection methods.

• Obtain more accurate MITRE ATT&CK mappings based on the latest threat intelligence.

• Improve threat hunting strategies by recognizing recurring tactics used in nation-state attacks.

For example, a BlackEnergy sample first analyzed in 2016 may not have had MITRE ATT&CK mappings. By reanalyzing it in 2022, researchers could extract more detailed attack techniques for better detection and response.

Key Considerations and Limitations

While Hybrid Analysis is a powerful tool, researchers should keep in mind:
✔ Public Availability of Samples: Any uploaded sample becomes publicly accessible, so avoid submitting malware containing sensitive company data.
✔ Sandbox Evasion Techniques: Some malware detects analysis environments and does not execute properly, requiring alternative analysis methods.
✔ Report Date Awareness: Older reports may lack modern attack mapping features, making reanalysis necessary.

Conclusion: Strengthening Threat Hunting with Hybrid Analysis

• Analyzing nation-state malware like BlackEnergy is crucial for understanding adversarial tactics and strengthening cybersecurity defenses. By leveraging Hybrid Analysis, security teams can:
  Quickly map attack techniques using MITRE ATT&CK.
• Extract actionable intelligence for threat hunting.
• Identify patterns in cyber threats targeting specific industries.

This process provides an efficient way to analyze malware end-to-end, helping organizations stay ahead of evolving cyber threats.

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