🚩 Capture The Flag (CTF)

Capture The Flag (CTF) competitions challenge participants to find and capture "flags"—not physical ones, but special strings of text hidden within the competition environment. These flags serve as proof that a challenge has been successfully solved.

For example, in the Fl4gHunt competition, flags followed the format:
F4H{code}

The Global CTF Community

Since 2012, the platform CTFtime (opens in a new tab) has been a central hub for CTF enthusiasts worldwide. It provides:

• A calendar of upcoming competitions
• Writeups with solutions to past challenges
• A leaderboard ranking top CTF teams

However, CTFtime only supports team-based competitions, which is why Fl4gHunt is not listed there.

CTF Formats

There are different types of CTF competitions, each offering a unique challenge:

🎯 Jeopardy-Style

The most popular format. Participants solve static challenges in predefined categories such as:

• 🕵️ Forensics – Analyzing digital evidence
• 🔄 Reverse Engineering – Breaking down compiled programs
• 🌐 Web Security – Exploiting web-based vulnerabilities
• 🔑 Cryptography – Cracking encrypted messages

⚔️ Attack-Defense

In this format, teams are divided into:

• 🔴 Red Team (attackers) – Find and exploit vulnerabilities
• 🔵 Blue Team (defenders) – Secure their own systems

This creates a realistic cybersecurity battle between offense and defense.

👑 King of the Hill

A less common but exciting format. Teams compete to control a specific resource for as long as possible while others try to take it over. Constant attacks make maintaining control a real challenge!