Hrmmm, secure your OpenSSH server, you must, young Padawan. Three simple steps to follow, there are:

00) Password Authentication, a weakness it is. SSH Keys, use you must
01) Root Login, a vulnerability it presents. Restrict it, you shall
02) OpenSSH, updated it must be kept

Remember, young Padawan, security a journey is, not a destination. Vigilant, you must remain.  See https://www.cyberciti.biz/tips/linux-unix-bsd-openssh-server-best-practices.html for more info. #unix #linux 

 And eliminate week and insecure ciphers! forbid them