Writeup: https://kumaus.github.io/HHC2019-writeup/
Homepage: https://holidayhackchallenge.com/2019/
This was the first time for me to seriously participate in the HHC. I was greatly honoured that the writeup was given a Super Honorable Mention. SANS keeps the challenges online indefinitely, which makes HHC really great to sharpen your teeth even after the event.