TerraMaster NAS TOS <= 3.0.30 Unauthenticated RCE as Root

Recently I bought a TerraMaster F2-420 NAS from Amazon in order to store my private code, backups and this kind of stuff. As soon as it arrived I started to play with its web interface and eventually I wanted to see how it was implemented, moreover I was curious to see if I could find any remotel...