Would you consider doing a video on locking down a Linux laptop? Really interested in your best practices. I’ve picked up bits and pieces in different videos, but I’m really interested in your process and how you do it.
I will be doing a video on this soon, but Linux comes fairly secure out of the box and the problem can come up when you start installing services that open up the system, such as sharing files or adding an SSH server. On a new Debian / Ubuntu based install you can install ufw firewall.
sudo apt-get install ufw
sudo ufw enable
The default config will block all inbound traffic and you can fine tune to allow things like ssh. To make things easier you can install a GUI for ufw.
sudo apt-get install gufw
For audits, maybe look at Lynis.
It is also good to be interested in AppArmor.
A simple firewall like “ufw” (iptables / nftables) is an extreme minimum. Although you can look at solutions like OpenSnitch, Douane … and so on. Imho relying only on ordinary fw in 2019 in the context of an individual machine is a bit like not closing locks in the door …
I do not like very much when an app without some visibility and consent sends something into the network.
A typical argument is that you do not run applications you do not trust. But this is not a solution at all.
Personally, I would like the “Application Based Firewalls” solutions to be more popular in the linux world as it is in the world of Windows.