Writeups & Tutorials

  • CryptoGolf

    Our task is essentially the following: perform at most lim1 – 1 encryptions and send the decrypted challenge, so we need to uncover the secret in 128 – 1 == 127 queries.

  • SpaceY Dump

    SpaceY Dump was a fairly high marks question in the Misc category for UMDCTF 2020. The goal is to try and unmask the anonymous Twitter user claiming responsibility for a hack and subsequent data leak.

  • PIL

    We have a main and 2 functions. GetNextPiDigit’s purpose is obvious, although we originally had some confusion over whether the one-million-digits.txt started with 3.14, 314, or 14.

  • RubiksCBC

    I implemented this really cool Rubiks CBC encryption algorithm and tested it on a document with my flag in it, but my dog ate my hard drive so I couldn’t decrypt the file :(

  • SignStealingSoftware-P2

    As a result of the LFI, we have the ability to view a file’s content, but we don’t have the ability to locate files that we seek in the system. We thought of 2 different possible approaches: