DawgCTF is an annual cybersecurity competition hosted by UMBC's CyberDawgs. The 2025 edition featured a variety of challenges across multiple categories including cryptography, web exploitation, reverse engineering, OSINT, and more.
Below are detailed walkthroughs of the challenges I solved during the competition, organized by category.
Deciphering a message encoded with the "Birds on a Wire" cipher from a simple image.
Implementing the inverse of a mathematical pairing function to decrypt the flag.
Exploiting a common modulus attack to recover the factors of an RSA key and decrypt the flag.
Analyzing a Linear Congruential Generator (LCG) to predict passwords and gain admin access.
Finding a flag hidden in plain sight on the competition's Discord server.
Revealing a hidden message in the spectrogram view of an audio file.
Demodulating an Amplitude-Shift Keying (ASK) signal to extract the hidden flag.
Finding a hidden key in a Wikipedia edit to decrypt a Vigenère cipher with Star Trek and Star Wars references.
Using the what3words geolocation system to identify a military installation.
Identifying a famous chess game from a board position to discover "Kasparov's Immortal."
Identifying a specific grocery store location in Berlin based on provided images.