sudo adduser K5Y0
echo SomeStupidPassword | passwd K5Y0 --stdin
echo "K5Y0" | sudo tee -a /etc/vsftpd/user_list
sudo mkdir -p /home/K5Y0/ftp/upload
sudo chown -R K5Y0: /home/K5Y0/ftp
sudo chmod 440 /home/K5Y0/ftp
sudo chmod 440 /home/K5Y0/ftp/upload

systemctl restart vsftpd