To find a good write-up, you should look for "KringleCon 2021" or "CyberDefenders Noel" on platforms like:

HTB Sherlocks Write-up regarding a "Neural Noel" challenge.

If this is a specific CTF, searching for "Noel 2021 CTF flag" or "SANS 2021 Noel" in a search engine may yield the precise solution. If you can share: