When it comes to learning cybersecurity, there’s a way to do it that feels less like studying and more like a high-stakes game. I’m talking about Capture the Flag competitions. Out of curiosity, I dived into this interesting world and, before I realized it, I got totally hooked.
What Is a CTF?
A CTF, short for Capture the Flag, is a type of competition designed to challenge participants in the field of computer security. The goal is to capture virtual flags, often in the form of text in the leet format. These flags are hidden within various systems, applications, or files. By solving security-related problems, you can retrieve these flags and earn points by submitting them.
At its core, a CTF is both a learning tool and a game, making it a fun and interactive way to dive into cybersecurity, whether you’re a beginner or a seasoned professional. CTFs usually come in three categories: Jeopardy-style, Attack-defense, and Mixed or King of the Hill.
Jeopardy-style is the most common and popular CTF format. Participants are presented with a list of security-related puzzles or problems across different categories, such as cryptography, binary exploitation (also known as pwn,) web security, reverse engineering, OSINT, forensics, and others. Each problem has a hidden flag, and points are awarded for solving each. The more difficult a problem, the higher the points offered for it. It’s similar to quiz shows where teams solve challenges at their own pace.
Attack-defense is a more advanced and competitive category. Each team needs to defend its own system while simultaneously attacking the opponent’s system. This type of competition reflects real-world cybersecurity operations and requires both offensive and defensive skills.
King-of-the-Hill categories combine both attack and defense, but they often have a competitive element where participants or teams fight to control a specific machine or set of machines. The goal is to exploit vulnerabilities, patch systems, and maintain access to the machine.
It’s the Fun Way to Learn About Computer Security
One of the biggest appeals of CTF competitions is that they provide an enjoyable, hands-on way to learn about different computer security concepts. Traditional methods of learning cybersecurity often involve dense reading materials, theoretical coursework, or rigid training environments.
CTFs, in contrast, transform the complexities of cybersecurity into a series of fun challenges and puzzles. Such a gamified structure makes learning much more engaging than sitting through lectures or reading textbooks. The sense of adventure, where you solve real-world problems and capture digital flags, creates an immersive experience that is both thrilling and educational.
The hands-on nature of CTFs is what sets them apart from other learning methods. Instead of passively absorbing information, players are forced to solve problems, think outside the box, apply tools, and experiment with different techniques. This “learn by doing” approach is proven to be one of the most effective ways to retain information.
For example, instead of reading about SQL injection, participants are given a web application that is vulnerable to that attack. They can then engage with the application and try to retrieve sensitive information through trial and error.
Another great park of CTFs is that they cater to all sorts of people because solving CTF problems requires a wide range of diverse skills. Most CTFs include challenges of varying levels of difficulty, making it easy for newcomers to get started without feeling overwhelmed. Beginners can start with simple challenges, like basic encryption problems or small web vulnerabilities, while advanced participants tackle more complex issues like binary exploitation or system forensics.
How to Get Started With CTFs
If you’re intrigued by the idea of playing CTFs and want to dive in, getting started is easier than you might think. There are numerous platforms available that cater to beginners, and with the right strategy, you can steadily build your skills while having fun. Here’s a list of platforms you can go to for the basics.
picoCTF
Created by Carnegie Mellon University, picoCTF is an excellent starting point for beginners. It’s designed as an interactive game with beginner-friendly challenges in categories like general skills, cryptography, forensics, web, etc. Other than challenges, it also includes guided tutorials for each category and educational resources, making it ideal for those who are completely new to CTFs or cybersecurity in general.
CTFLearn
CTFLearn is a community-driven platform with a wide range of CTF challenges that cater to different skill levels. The challenges are categorized, making it easy to explore various topics like reverse engineering, steganography, or forensics. It’s a great way to practice at your own pace and even contribute your own challenges as you progress.
CTF101
CTF101 is a free, beginner-focused platform that teaches the fundamentals of CTF competitions. The site provides comprehensive explanations of key topics for different categories with examples and different scenarios. It’s a great place to build foundational skills before tackling more complex platforms.
TryHackMe
TryHackMe is a platform designed for learners of all skill levels. It offers interactive labs and guided tutorials that walk you through real-world security scenarios. Beginners will appreciate the step-by-step guides, while more advanced users can skip directly to the difficult rooms. TryHackMe focuses on various topics, from basic hacking to penetration testing and network security.
Hack The Box
Hack The Box (HTB) is a popular platform for more advanced CTF players. HTB provides real-world security challenges, with vulnerable machines that you can hack into, patch, and test. While it has a steep learning curve, it’s an ideal place to develop practical, hands-on skills once you’ve gotten a handle on the basics. HTB also includes a robust community where users share tips and write-ups.
With that, you can get busy playing. However, for better success, you need to follow a good strategy. First, start with the basics. Learn how to use Linux and the command line. Learn how the web works, get some networking skills, read cryptography concepts, and get a hold of a few programming languages. Before you know it, you’ll be up for some good challenges. Learn the essential tools and command-line utilities you’ll need to tackle different problems.
Failing to solve a challenge isn’t a setback, it’s a learning opportunity. If you’re unable to solve a problem, try to look for hints (often provided in the question.) Read write-ups of players who’ve already solved that challenge. While you do that, don’t just skim through the solution. Try to read the mindset of the author. How did he find the solution? What steps did he take before finding the flag? This will help you become a better player and start thinking like a hacker.
My Experience Playing CTFs
I’ve been playing CTFs on and off for some time now. When I first started, I didn’t expect much. I was just curious, dipping my toes into the world of cybersecurity to see what it was all about. But it didn’t take long for CTFs to evolve from a casual pastime into a full-blown hobby, and then into something even more, almost a passion project.
What surprised me the most was how much I learned in such a short period. Each challenge exposed me to new concepts and tools, teaching me things I likely wouldn’t have encountered in traditional learning environments. Throughout this journey, I found that I’m particularly drawn to OSINT, web security, and forensics challenges. There’s something deeply satisfying about uncovering hidden information, exploiting stuff, and digging through artifacts.
Playing and Learning at the Same Time
Looking back, what started as a simple curiosity has turned into a fulfilling part of my life. CTFs have taught me a great deal about computer security, sharpened my problem-solving skills, and trained me to think differently. It’s been an incredible ride, and I can’t wait to see where this journey takes me next.