Write-Up Advent of CTF 2020 Challenge 1


The NOVI University Of Applied Sciences is offering an Advent CTF challenge for December 2020. The CTF is created by our community member of the and Chief Lecturer for Cyber Security at the NOVI University, Arjen Wiersma. If you want to participate in these CTF challenges, you can create an account on the website

Challenge 1

  • Description: All starts should be easy.
  • Points: 100

This challenge has this URL: So, I visited this URL.


Well, do I have to guess the password? Let’s first check the source code of this website. And, it looks like the one base64 uncoded flag is present in the source code. This looks a lot like challenge 0 🙂



After decoding this Base64 encoded string, I got the password to log on. So, no password guessing, no Python script creation to password spray, just reading the source code. Sometimes it’s as simple as it seems

~$ echo "YWR2ZW50X29mX2N0Zl9pc19oZXJl" | base64 -d 

After logging in on the website as Santa, I got the flag.


Thanks for reading!

This post is licensed under CC BY 4.0 by the author.