Some challenges were hosted on our infrastructure. They are now available as Docker images which you can download and run on your own computer. If you want to solve the challenges in the same way as the participants of the CTF, you should treat these Docker instances as blackboxes and avoid peeking in them.


You are the last person on planet Charvis 8HD. Everyone has decided to leave because Charvis 9HD is the hipper place to live. As the last person to leave, your Captain sent you the following instructions:

"Make sure you enable the Charvis 8HD Defense System (CDS) after taking off in your spaceship."

However, you misread the instructions and activated the CDS before leaving the planet. You are now stuck on this planet. Can you figure out how to manually disable the 10 defense systems (C1 thru C10) which comprise CDS in order to safely take off?

Thankfully, Charvis 8HD does not have strong dust storms and you will not need to travel 2,000 miles in a rover.


├── programming
|   └── C1: dot-n-dash
├── cryptology
│   ├── C2: flipping bits
|   └── C4: leaky power
├── image processing
|   └── C3: shredded
├── gdpr
|   └── C5: de-anonymization requires Docker
├── reverse
│   ├── C6: gates of hell requires Docker
│   ├── C7: gofuscated
|   └── C9: postfuscator
└── math
    ├── C8: captcha requires Docker
    └── C10: fixed point requires Docker


Write Ups

See also

Work_at_Square(1), Privacy_policy(1), Code_of_conduct(1)

Square, Inc. (c) CHALLENGES(2018)