Started off by
- Enabling unattended updates
- Enable only ssh login with key
- Create user with sudo privileges
- Disable root login
- Enable ufw with necessary ports
- Disable ping
- Change ssh default port 21 to something else.
Got the ideas from networkchuck
Did this on the proxmox host as well as all VMs.
Any suggestions?
If someone or something malicious gets a shell account on my systems, then it at least stops them doing anything system-wide. And yes, if a script is going to request admin rights to do something, it'll stop right at the
sudo
prompt. Passwordless, it could do stuff without you even being aware of it.Whether or not this is a line of defence at all is open to debate.