

Some upgrades require human input like when core service config files upgrades are offered. (ex. would like to update /etc/samba/smb.conf with the maintainer’s version or keep your own?)
In my experience this can occasionally cause background apt processes to hang while they wait for your answer to that kind of question. There is a debconf trick you can try. debian_frontend=noninteractive. You can create your own cronjob, as root, that runs a script with this export command, apt update, then apt dist-upgrade -y.
Ignore the idiot posting about this RAT.
If you want to secure your Linux system, use ClamAV, a local firewall like UFW or even opensnitch for a start. Also use your head when adding apps to your system. Stick to the official repos from your distro. Things like Arch’s AUR, random PPAs in Ubuntu and any random github project are going to be much riskier by their very nature so act accordingly.
If you need to risky stuff, do it a VM and network that guest into a private internal network that can only exit over a companion PFSense VM that is dual homed to the regular LAN and the private internal network. Take a snapshot of the risky guest before you use it in a session and when you are done, roll back to your clean snapshot.
Store your passwords in something like Keepass(strong master password!) and then use syncthing to push copies of the database to at least one other box locally or in the cloud if you really have to.