HackTheBox - Napper

Step-by-Step Tutorial:

1. Understanding the Malware and Goals:

   • The video discusses a unique box called Napper on HackTheBox.
   • The box involves reversing malware, particularly the Nap Listener malware discovered by Elastic.
   • The goal is to reverse engineer a Go binary, extract passwords from LAPS, and gain administrator access to the box.

2. Initial Enumeration:

   • Use the command nmap -sC -sV -oA [output_directory] [IP_address] to scan the target machine.
   • Analyze the response to determine open ports and services running on the box.

3. Exploring the Web Application:

   • Identify HTTP and HTTPS services running on port 443.
   • Analyze SSL certificates to gather information about the organization maintaining the website.

4. Discovering Internal Services:

   • Look for internal services like internal.napper.htb.
   • Attempt to log in using default credentials or basic authentication methods.

5. Investigating Malware Research Notes:

   • Explore blog posts related to internal malware research notes.
   • Focus on understanding the Nap Listener backdoor and its functionality.

6. Exploiting the Backdoor:

   • Analyze the backdoor mechanism that loads and executes assemblies based on specific parameters in the URL.
   • Use the information to exploit the backdoor and gain access to the internal system.

7. Decryption and Access:

   • Extract encrypted data from the system and decrypt it using the provided method.
   • Gain access to the system as an administrator by leveraging the decrypted information.

8. Analyzing Elastic's Post:

   • Investigate Elastic's blog post detailing threat actors using the backdoor.
   • Understand the decompiled output of the backdoor to set up a custom router application.

9. Setting Up the Environment:

   • Install necessary tools like Mono and set up the development environment for reverse engineering.

10. Developing Custom Solutions:

• Create a Go application to interact with the Elastic API and extract required information.
• Implement encryption and decryption mechanisms to handle sensitive data.

11. Testing and Exploitation:

• Test the developed application against the target system to retrieve critical data.
• Exploit vulnerabilities to gain privileged access and achieve the objectives of the box.

12. Final Steps and Cleanup:

• Ensure all actions are reversible and do not cause harm to the target system.
• Document the process and findings for future reference and analysis.

By following these steps, you can effectively replicate the actions demonstrated in the video and gain insights into reversing malware, exploiting vulnerabilities, and achieving administrator access on the Napper box on HackTheBox.