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FIRST CTF — Capture the Flag

A permanent, open Capture-the-Flag platform by the FIRST community and the SecLounge SIG. Incident-response-inspired challenges you can solve any time, at your own pace — for learning and for fun.

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About the CTF

The FIRST Challenge is a series of technical problems designed to provide a fun opportunity to use creative technical problem-solving to tackle incident-response-inspired challenges. This instance is a permanent, always-available collection of challenges — those previously offered at FIRSTCON / SecLounge editions plus new ones for training and fun.

Challenge categories

Network Cryptography Reverse engineering Programming Forensics Miscellaneous Puzzle


How it works

Play as an individual

You compete as a single player — there are no teams on this instance.

Always on

This is a permanent instance. Register once and solve challenges whenever you like, at your own pace.

Points per solve

Each challenge is worth 100–500 points, awarded on a correct flag. The order in which you solve them does not matter.

Hints available

Many challenges offer hints. Most hints cost points (deducted from your score); some are free. The cost is always shown before you unlock a hint.

Just for fun

There are no prizes. The scoreboard is there for personal progress, practice and bragging rights.

Fair play

The organising team (SecLounge SIG) reserves the right to exclude anyone engaged in inappropriate activity. Any dispute is resolved by the SIG.

Tips — pay close attention to flag formatting (spaces & special characters); multi-part challenges reveal later parts only as you solve the earlier ones; everything is designed to be solvable with standard free / open-source tools — a Linux workstation or a forensics VM such as REMnux or SIFT is enough.

Be patient, persistent, and have fun!


Our sponsors

This permanent FIRST CTF instance is made possible by the generous support of: