Cryptax
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Description We are given a hardware badge with no particular instruction, but we know there are CTF challenges on it.
Investigation The front of the badge has Leds, no screen. The back of the badge has a USB connector, a few exposed pins, a battery holder, and underneath a push button. Also, Morse code for numbers is shown on the back.
When we power on the badge, it blinks, and then nothing happens.
Break my stream Description CrypTopia is testing their next gen encryption algorithm. We believe that the way they implemented it may have a flaw…
We are given a Python file main.py.
Code analysis The flag is encrypted with a key, which is selected randomly:
1 2 flag = b"XXX" key = os.urandom(256) The encryption consists in a XOR with a keystream derived from the key:
1 2 3 4 5 6 7 def encrypt(self, message): result = [] for char in message: key = next(self.
This is a write-up for the following challenges:
Containers Quantum Kraken Device - the Skeleton Key. Calibration 1 and 2. Internet Services Automation 101 (Hackademy track) Sailor Kidz (part with “A” ciphertext) Containers The theme of this CTF was a cruise ship, CVSS Bonsecours (conference and CTF taking place at Marché Bonsecours in Montréal).
Description:
While the Bonsecours is obviously a cruise ship, civilian ships can be chartered to carry cargo in containers.