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What is this?

This repository (currently) houses two projects:

  • CTFlex, short for ‘CTF-lexible’: a reusable CTF framework written as a Django app.
  • PACTF Web: a website for PACTF that uses CTFlex.

PACTF itself, short for ‘Phillips Academy CTF’, is a PvE CTF targeted at high schoolers.

Don’t know what a PvE CTF is? Read on!

What is a CTF?

CTFs, short for ‘Capture the Flags,’ are a type of Computer Security competition where “you hack, decrypt, reverse, and do whatever it takes to” capture secret answer strings called ‘flags’ (to quote PicoCTF’s website).

In a PvP CTF, teams get assigned systems and try to hack into other teams’ systems, whereas in a PvE CTF, teams solve puzzles all written and set-up by the contest organizers. Most high-school CTFs (including PACTF) are PvE, and this documentation only talks about PvE CTFs.

To get flags, you solve problems, and once you solve one, you should end up with, among other things, a string of text. This string is usually human-readable, and it almost always adheres to a predictable format, like flag{<this_part_changes>}. Once you think you’ve captured the flag, you can submit it online next to the problem’s description. Your submission will be graded, and, if it is correct, you will earn points and possibly unlock more problems!

You sign up for CTFs as part of a team of 1–5 players. Mosts CTFs award prizes to top scorers if your team is eligible based on its members’ locations, educational background etc. For example, for PACTF, your team has to consist of American middle- or high-schoolers to be ranked on the scoreboard and win prizes. The scoreboard is just that: a ranking of eligible teams.

PACTF/CTFlex is different

From PACTF’s website:

Experienced CTFer? Or new to Capture The Flags? Either way, want to solve problems and win prizes without spending fourteen consecutive days on a CTF? Check out PACTF.

Instead of a two-week sprint, PACTF will have three rounds, each one week long. During each round, your team will be able to pick any two-day span to grab as many flags as you can! Choose wisely: Once your two days run out, you won’t be able to score more points in that round.

Don’t worry about being too slow, though! Even if your two-day timer is over, you can still test your skills against problems in previous rounds.

There are scoreboards for each individual round, and there is an overall all-time scoreboard. Prizes will be given to the top-ranking teams of the individual rounds and the overall CTF, so whether you are a specialist or an all-rounder, there's something for you!

PACTF enjoys this feature of rounds and timers grâce à CTFlex.

Who are you?

Want to solve computer security puzzles for fun and prizes?

Head on over to PACTF’s website!

Want to host your own CTF?

Then you’ve have come to the right place!

By using CTFlex, you will be able to focus on what’s important to your CTF like writing problems, not getting bogged down with the minutiae of of figuring out email password resets etc.

You need not be familiar with Django or proficient with Python to use CTFlex successfully.

Now go check out the host documentation!

Want to hack on CTFlex or just know how it works?

That’s awesome! Check out the developer documentation.

Who are we?

We are bunch of high-schoolers who participated in their first CTF in the Fall of 2014 and have since been driven to bring that same rewarding experience to everyone. We are:

If you are using CTFlex and PACTF, we would love for you to get in touch for providing feedback or asking for support.

We were able to bring CTFlex and PACTF to you thanks to support from our school, Phillips Academy, Andover.