How to disable a malicious kick off service

I'm using a Linux server with my whole team together. We all have sudo permission. As we know, we can kick someone off easily: who -u will list all of ssh logins with their PIDs and then kill -9 anyone. Now let's say some bad man wrote a bash script, which would loop all of login users and kick off all of them: while true do # kill -9 each PID in who -u done Also, the bad man configured the bash script with systemd so that it would be started automatically while booting or rebooting. Now, I think nobody could remote login anymore. My question is if there is some technique to solove this problem without reinstalling the OS.