# Challenges

Web Hard

Executioner 1

A command execution service with a filter. Find a way to run what you need despite the restrictions.

250 points 3 solves

Web Hard

Dev Academy

NovaDev Academy just launched their new website. They are running a suspiciously specific version of PHP.

250 points 2 solves

Web Medium

Decimals

A number that is simultaneously less than and greater than a threshold. PHP has some interesting ideas about numbers.

150 points 4 solves

Web Hard

Curse Hunter (4)

When you arrived at the location, a massive surge of curse energy engulfed you, triggering a domain expansion. Your a...

250 points 0 solves

Web Computer: You will analyse downloaded files, which usually needs a computer. Hard

CTF Market

Welcome to the CTF Market! Browse products, apply coupons, and upgrade your account. Every good shop has its weak spots.

250 points 0 solves

Crypto Computer: This challenge connects with nc or SSH, which needs a terminal. Medium

Predictable Randomness

Randomness is only as strong as the algorithm behind it.

150 points 2 solves

Web Medium

Circus 2

String comparison protects the flag. But not all comparisons behave the way you expect.

150 points 2 solves

Web Medium

Circus 1

Two values must produce the same hash, but they cannot be equal. The comparison operator holds the key.

150 points 3 solves

Web Computer: This challenge connects with nc or SSH, which needs a terminal. Medium

By Proxy

A web proxy forwards your requests to an internal service. What happens when you control where it goes?

150 points 2 solves

Misc Computer: This challenge connects with nc or SSH, which needs a terminal. Medium

Bear Ninja Cowboy 4

The game adapts to your play style. Can you outsmart an opponent that learns from your moves?

150 points 1 solves

Misc Computer: This challenge connects with nc or SSH, which needs a terminal. Medium

Bear Ninja Cowboy 3

The computer picks its moves using a random number generator. But is it truly random?

150 points 2 solves

Misc Computer: This challenge connects with nc or SSH, which needs a terminal. Easy

Bear Ninja Cowboy 2

Another round of Bear-Ninja-Cowboy. The rules seem familiar, but the input handling has a subtle flaw.

50 points 3 solves

Misc Computer: This challenge connects with nc or SSH, which needs a terminal. Easy

Bear Ninja Cowboy

A rock-paper-scissors variant where Bears, Ninjas, and Cowboys battle it out. Win 30 rounds in a row to claim the flag.

50 points 4 solves

Web Easy

Basics 6

Another gallery with server-side image loading. Look beyond what the page shows you.

50 points 9 solves

Web Easy

Basics 5

A number guessing game with client-side validation. But does the server agree with the rules?

50 points 11 solves

Web Easy

Basics 4

The server remembers who you are between requests. But who decides what it remembers?

50 points 10 solves

Web Easy

Basics 3

A gallery page displays images from the server. Is what you see really all there is?

50 points 11 solves

Web Easy

Basics 2

The server only trusts a specific type of visitor. Can you convince it you belong?

50 points 12 solves

Web Easy

Basics 1

A simple login page guards a secret. Sometimes the answer is hiding in plain sight.

50 points 14 solves

Web Medium

Baby PHP

A PHP application that expects structured data in a very specific format. Can you speak its language?

150 points 5 solves