Recent Posts

  • UMassCTF 2022 - HatMash

    Cryptography – 500 pts (1 solve) – Chall author: Polymero (me)

    What do you mean “We think you spend too much time with matrices.”? It’s just a hash function, jeez…

  • HackPack CTF 2022 - Repeating Offense

    Cryptography – 443 pts (20 solves) – Chall author: Polymero (me)

    One-time oracles using RSA or Paillier are not a great idea due to those slippery mathemagicians… I would like to see them slip their way through RSA AND Paillier! After all, you cannot rob two banks at the same time. … What?

  • HackPack CTF 2022 - P(ai)^3

    Cryptography – 469 pts (15 solves) – Chall author: Polymero (me)

    Pai-ai-ai… My Paillier scheme seems to be broken and I stored my favourite flag in it. Please help me get it back, will you? Who could have guessed this would ever happen? … Me… I- I wrote it… yeah.

  • K3RN3LCTF 2021 - Total Encryption

    Cryptography – 500 pts (0 solves) – Chall author: Polymero (me)

    “To store our most embarrassing secrets, we created a Remote Secure Armoury protected by layered RSA encryption with XOR blinding. Never again will my friends be able to mock me for my use of words!”

  • K3RN3LCTF 2021 - Tick Tock

    Cryptography – 496 pts (6 solves) – Chall author: Polymero (me)

    “I chopped up my flag and hid it behind this simple key exchange. Try dlogging your way in if you are brave enough!”

  • K3RN3LCTF 2021 - Shrine of the Sweating Buddha

    Cryptography – 500 pts (0 solves) – Chall author: Polymero (me)

    “Welcome to the Shrine of the Sweating Buddha. Share the burden of your worries, my child ~~~.”

    Hint: share some (7) of your worries and perhaps your fortune will guide you to the flag.

  • K3RN3LCTF 2021 - HADIOR

    Cryptography – 499 pts (3 solves) – Chall author: Polymero (me)

    “HADIOR will hold the DOOR.”

  • K3RN3LCTF 2021 - Game of Secrets

    Cryptography – 500 pts (2 solves) – Chall author: Polymero (me)

    “John wants to play a game, a game of secrets. Recover his secret or be encrypted.”