Offensive Security Intro Walkthrough

Room : https://tryhackme.com/room/offensivesecurityintro#

Difficulty: Easy
Expected Time: ~15 minutes


📝 Overview#

In this beginner-friendly room, you’re introduced to Offensive Security and get hands-on experience hacking a simulated web application—FakeBank—using the directory brute-forcing tool Gobuster. By mimicking a hacker’s actions, you’ll practice ethical hacking in a safe, legal environment.


Task 1: What is Offensive Security?#

You’re asked:

Which of the following options better represents the process where you simulate a hacker’s actions to find vulnerabilities in a system?

  • Offensive Security
  • Defensive Security

Answer: Offensive Security

Reason: It involves simulating hacker behavior to uncover vulnerabilities before a cybercriminal does.


Task 2: Hacking Your First Machine#

Step 1: Start the Machine#

Launch the VM for the FakeBank application and open the browser and terminal interface.

Step 2: Open the Terminal#

On the right side of the interface, click the Terminal icon to start typing commands.

Step 3: Use Gobuster to Discover Hidden Directories#

Run:

gobuster -u http://fakebank.thm -w wordlist.txt dir
  • -u specifies the target URL (http://fakebank.thm)
  • -w specifies the wordlist (wordlist.txt)
  • dir tells Gobuster to use directory brute-forcing mode

Example output:

/images (Status: 301)  
/bank-transfer (Status: 200)  

Step 4: Access the Bank Transfer Page#

Navigate to:

http://fakebank.thm/bank-transfer

This is the hidden admin portal that allows money transfers.

Step 5: Exploit the Vulnerability#

Use the admin interface to transfer $2000 from account 2276 to 8881.
After submitting, you should see a “Success, transfer complete” message.
Return to your account view to see your updated balance.
The page will display the room’s flag:

Flag: BANK-HACKED

Step 6: Terminate the Machine#

Click the red Terminate button in the TryHackMe interface to stop the VM.


Task 3: Careers in Cyber Security#

This section explains various roles within offensive security:

  • Penetration Tester – Finds and exploits security vulnerabilities.
  • Red Teamer – Simulates real-world attacks to test security defenses.
  • Security Engineer – Designs and maintains systems and controls to prevent cyberattacks.

No answers are required—just read and proceed.


Summary Table of Commands & Steps#

StepActionCommand / Note
1Start the VMClick Start Machine
2Open terminalClick terminal icon on right pane
3Run Gobustergobuster -u http://fakebank.thm -w wordlist.txt dir
4Discover hidden pageLook for /bank-transfer
5Perform transferNavigate to /bank-transfer, send $2000 from 22768881
6Capture flagLook for “BANK-HACKED” message on account page
7Terminate VMClick Terminate button

Final Thoughts#

This room is an excellent hands-on introduction to ethical hacking. You’ll learn:

  • Why thinking like a hacker (Offensive Security) is vital
  • How to use Gobuster for web directory discovery
  • The real-world impact of unsecured admin portals

Tips#

  • Always read the task instructions carefully—understanding why something is done is as important as knowing how.
  • Practice with the command line often—it builds fluency with tools like Gobuster.
  • After completing, try more TryHackMe rooms to explore other facets of cybersecurity.

Adapted from Jery0843/TryHackMe under MIT.

Find us elsewhere

Merch, stickers, and moreSupport the work at the Solvere Labs shop