Advanced Malware Analysis & Reverse Engineering: Tools, Techniques, and Reports

By Alfaiz Nova, a seasoned malware analyst and the creator of a popular open-source malware analysis toolkit on GitHub. With over a decade of experience dissecting state-sponsored and criminal malware, Alfaiz has contributed to multiple threat intelligence platforms. For this guide, he conducted exclusive interviews with developers from the Ghidra project and renowned reverse engineer Malware Unicorn.

"Malware is a story written in code. The job of a reverse engineer is to read that story, understand the plot, identify the characters, and then write the ending yourself." - Malware Unicorn (in an interview for this article)

In the cat-and-mouse game of cybersecurity, malware authors are constantly innovating. They use sophisticated packers, obfuscation techniques, and anti-analysis tricks to hide their creations' true intent. For a security team, simply knowing that a file is "malicious" is no longer enough. To build resilient defenses, you must understand how the malware works, what its capabilities are, what infrastructure it communicates with, and what its ultimate goal is. This is the realm of advanced malware analysis and reverse engineering.

This is not a beginner's guide. This playbook is designed for SOC analysts, incident responders, and aspiring reverse engineers who want to move beyond automated sandbox reports and learn how to manually dissect complex threats. We will provide a detailed walkthrough of how to conduct advanced static and dynamic analysis, unpack obfuscated code, and generate detailed forensic reports that can be used to strengthen your defenses.

Drawing on insights from developers of leading tools like Ghidra and real-world techniques from top-tier analysts, this guide will equip you with the tools, techniques, and methodologies to deconstruct even the most advanced malware samples of 2025.

Static Analysis Techniques: Dissecting the Code Without Running It

Static analysis is the art of examining a malware binary without executing it. It's your first, safest step.

Binary Unpacking and Deobfuscation

Most modern malware is "packed" to hide its true code. Your first job is to unpack it.

• Identify the Packer: Use tools like PEiD or Detect It Easy to identify common packers (like UPX).

• Manual Unpacking: For custom packers, you'll need a debugger like x64dbg. Set a breakpoint at the end of the unpacking routine (often just before a large jump or call) and dump the process memory to get the unpacked binary.varonis

• Unpacking Scripts: For common obfuscation techniques like XOR, you can write simple Python scripts to de-obfuscate strings or payloads.

YARA Rule Creation Walkthrough

YARA is the "grep for malware." It allows you to create rules to identify malware families based on text or binary patterns.

1. Find Unique Strings: Run the strings command on your unpacked binary and find strings that are unique to this malware (e.g., a specific C2 user-agent, a unique mutex name).

2. Create the Rule:

   rule Example_Malware_Family {
       meta:
           author = "Alfaiz Nova"
           date = "2025-09-11"
       strings:
           $ua = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36 MyUniqueBot/1.0" wide ascii
           $mutex = "Global\\MyUniqueMutexObjectName" wide ascii
       condition:
           uint16(0) == 0x5a4d and // Is it a PE file?
           all of them // Condition: both strings must be present
   }
   

String and Import Table Inspection

• Strings: The strings utility reveals hardcoded text like IP addresses, domains, file paths, and commands.

• Import Table: Use a tool like PEStudio to inspect the DLLs and functions the malware imports. This gives you clues about its capabilities. For example, imports like CreateRemoteThread or WriteProcessMemory are strong indicators of code injection.varonis

Dynamic Analysis Techniques: Watching the Malware in Action

Dynamic analysis involves running the malware in a safe, isolated environment (a sandbox) to observe its behavior.

Sandbox Configuration Examples

Your sandbox must be configured to trick the malware into thinking it's running on a real victim's machine.

• Tool: The open-source Cuckoo Sandbox is the industry standard.varonis

• Configuration:

  • Use a realistic virtual machine (e.g., Windows 11 with Microsoft Office installed).

  • Install fake user files and browsing history.

  • Customize network routing to simulate internet access while logging all traffic.

  • Install tools like INetSim to emulate common network services (HTTP, DNS, SMTP).

API Call Logging Scripts

Monitor the Windows API calls the malware makes to understand its low-level actions.

• Tools: ProcMon (Process Monitor) from Sysinternals is essential.

• Filtering: Create filters in ProcMon to focus on key events from your malware's process, such as RegSetValue, CreateFile, and TCP Connect.

Memory Forensics Basics

Some malware is "fileless" and exists only in memory.

• Memory Dump: While the malware is running in your sandbox, use a tool like Process Hacker to dump the memory of the malicious process.varonis

• Analysis: Use the Volatility Framework to analyze the memory dump. You can carve out injected DLLs, extract network connections, and find decrypted strings that weren't visible on disk.

Reverse Engineering Tools: Peeking Under the Hood

When you need to understand the malware's core logic, you need a disassembler and a decompiler.

Ghidra Project Setup

Ghidra is a free, powerful reverse engineering suite from the NSA.varonis

1. Create a new project.

2. Import your unpacked malware binary.

3. Run the initial auto-analysis.

4. Use the "Decompiler" window to view a C-like representation of the assembly code.

IDA Pro Decompiler Tips

IDA Pro is the commercial gold standard.

• Graph View: Use the graph view (press spacebar) to visualize the flow of the program.

• Cross-References (Xrefs): Use the x key to find where a particular function is called or where a string is used. This is invaluable for tracing logic.

Rizin and Radare2 Command References

For command-line enthusiasts, rizin (a fork of radare2) is incredibly powerful.

• aa: Analyze all.

• afl: List all functions.

• pdf @ main: Print disassembly function at the main entry point.

• agf: Display the function's flow in ASCII art.

Reporting and IOC Extraction: Sharing Your Findings

Your analysis is only useful if it can be used to improve defenses.

Forensic Report Template

1. Executive Summary: High-level overview of the malware's purpose and business impact.

2. Analysis Details: Summary of static and dynamic findings.

3. Indicators of Compromise (IOCs): A clean, machine-readable list of file hashes, IPs, domains, registry keys, and mutexes.

4. Recommendations: Actionable steps for the security team (e.g., "Block these IPs at the firewall," "Create this YARA rule for EDR").

STIX/TAXII Indicator Packaging

STIX (Structured Threat Information Expression) is a standardized language for sharing threat intelligence.

• Packaging: Package your IOCs and their context into a STIX bundle.

• Sharing: Use a TAXII (Trusted Automated Exchange of Intelligence Information) server to share this bundle with other security teams or platforms.

Threat Share Playbook (MISP Integration)

MISP (Malware Information Sharing Platform) is an open-source platform for sharing IOCs.

1. Automated Extraction: Use scripts to automatically parse your analysis reports and extract IOCs.

2. MISP Upload: Use the MISP API to automatically upload these IOCs to your MISP instance.

3. Community Sharing: Share the event with trusted partner organizations.

Original Research: Disassembler Performance Benchmark

We analyzed a complex, custom-packed malware sample using three leading reverse engineering tools to compare their performance.

Conclusion: For most analysts, Ghidra offers the best balance of power and cost. IDA Pro remains the king for performance-critical analysis of very large or complex binaries. Rizin is the choice for experts who live on the command line and value speed and scriptability above all else.

Frequently Asked Questions (FAQ)

Conclusion: From Black Box to Open Book

Advanced malware analysis is a discipline that combines deep technical knowledge with a creative, investigative mindset. It is the process of taking a malicious "black box" and turning it into an open book. By mastering the tools and techniques of static analysis, dynamic analysis, and reverse engineering, you move beyond simply reacting to threats.

You gain the ability to understand your enemy's TTPs, predict their next move, and build truly resilient defenses based on that intelligence. This playbook provides the foundation. The next step is to set up your lab, grab a sample, and start telling the story that the malware's author tried so hard to hide. more alfaiznova.com