Just a friendly word of caution: neither
sudo update-rc.d mono-xsp4 disable or even the
systemctl stop and
disable commands listed in the answer will outright disable this ridiculous service/process from running without a reboot. <== Just a heads up on that.
I nuked mine from the orbit just to be sure;
sudo update-rc.d mono-xsp4 disable && sudo systemctl status mono-xsp4.service && sudo systemctl stop mono-xsp4.service && sudo systemctl disable mono-xsp4.service
As stated, at this point the process is still running (!) -- check the status with (sudo)
htop if it's still there (in my case it WAS), press F3 and search for
mono, kill the process with F9 and choosing either
9 (SIGKILL) or
15 (SIGTERM) when the xsp4 command is highlighted.
Or, just go for the blanket solution:
sudo killall mono && sudo killall xsp4
You could also
sudo apt purge mono-xsp4, but that will uninstall ALL the Mono libraries and framework as well. Which in most cases is not the solution that you are after.
If you're concerned over the process after it's been disabled and seems to be no longer there, you can always view the
/etc/init.d/mono-xsp4 file contents, and maybe even scrub it out of the system altogether. Be careful when meddling with the files though, though; as mentioned in the other replies, you might end up breaking some of Mono's developer functionalities etc.
I agree with the other commenter who stated that the service should definitely be on-demand rather than on startup by saying that I'm not so sure either if it's a good practice to have those type of services running tbh, especially when you stumble into it during a routine LAN security scan. Many Mono related programs might have this in their dependencies, but having it on autostart by default is "a bit" of a bad practice IMHO. (I would've commented this as a reply, but I don't have enough reputation points for that). :|