Discover a proven pentesting roadmap for PENTESTER preparation with ethical-hacking labs, leveraging Hack The Box retired machines in the TJ Null List. Learn pentesting in 2025 with free Hack The Box.

I still remember the first time I spent hours chasing a vulnerability, only to discover that one mistyped character kept my exploit from working. That frustration — when theory meets real-world messiness — is where true skill is born. If you want to become a pentester, you have to practice — and practice hard. Nothing beats the lessons you learn by grinding through hands-on labs and CTF challenges.

Yet finding the right place to practice took me far longer than it should have. I began with the course labs I had bought, but they were stuck on outdated vulnerabilities inside a sandbox that felt more museum than battleground. It wasn’t until I started hanging out with seasoned hackers — people who lived and breathed this craft — that I heard whispers of Hack The Box Labs. I’ll admit, I dragged my feet on creating an account, but the day I finally logged in was the day my learning curve rocketed upward.

So once I finally stepped through the Hack The Box portal — and felt that surge of progress — I doubled down on it. Head straight to the HTB Labs section: dozens of ready-made machines are waiting for you. Start with the retired boxes first; detailed write-ups on Medium and step-by-step video walkthroughs from creators like IppSec act as built-in hints. Re-creating every exploit by hand will help you:

• Notice exactly where you mistyped a command.
• Absorb the underlying logic behind every action.
• Build the muscle memory that turns theory into real-world pentesting skill.

Don’t beat yourself up if you need write-ups to crack your first boxes; even Pablo Picasso learned by imitation. As a teenager, he spent countless hours at Madrid’s Prado Museum copying Velázquez, El Greco, and other masters. That disciplined mimicry sharpened his eye for line, color, and composition — so he could later shatter every rule and invent Cubism. Copy first, create later — so go ahead and follow those walkthroughs without guilt.

Simply typing each command out — and then re-typing it until it works — is your way of training both hands and brain. When you advance to structured courses like the Certified Penetration Testing Specialist, you’ll discover that the entire methodology is already etched into your mind.

I love diving into these labs; the hands-on work is easily the most rewarding part of an offensive-security journey. Lately, I’ve been grinding through Hack The Box’s Pro Labs, and I recommend tackling them once you’re fairly advanced or gearing up for a certification exam. Each Pro Lab mirrors a real enterprise network, giving you space to rehearse and refine dozens of techniques under near-live conditions.

• Deep AD Enumeration: Map out every domain controller, trust, and ACL.
• Real-World Vulnerability Exploitation: From unpatched services to custom web apps, Pro Labs challenge you to improvise.

If you’d like a preview — or just want to swap war stories — check out my Medium blog, where I document everything I learn from both certifications and Pro Lab runs.

A Targeted Roadmap: Leveraging the TJ Null List

Randomly jumping between machines can teach you some lessons, but following a defined roadmap makes your progress far more efficient. After countless hours spinning my wheels, I discovered the famous TJ Null List — a curated collection of boxes aligned with the major OffSec certifications you’re aiming for. One of my biggest mistakes during PEN-200 (OSCP) was not completing every machine on that list with rigor, which led to my failure on the first attempt and forced a retake. The TJ Null List not only simplifies your exam prep but also provides a solid path for any similar certifications you pursue

The TJ NULL LIST: NetSecFocus Trophy Room — Google Drive

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Looking back, the journey from fumbling through random machines to following a clear roadmap was a game-changer. By leaning into retired HTB boxes, I built the raw muscle memory every pentester needs. Then, when I discovered the TJ Null List, my approach shifted from haphazard attempts to laser-focused practice. Admitting that I failed my first PEN-200 (OSCP) attempt because I skipped machines on that list was humbling — but it also taught me the value of structure and perseverance.

Now, whenever I sit down at my keyboard, I know exactly which machines to tackle and why. Each box becomes a deliberate step toward mastering the skills that real-world engagements demand. And when I push into Pro Labs, I’m not just solving challenges — I’m rehearsing the same tactics I’ll use in a live environment.

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