[jkrejcha]

I think the main point here is that... well if you can help it, don't run untrusted software, since it's by definition not trusted. There are some times where you can't really get around it (JavaScript is an increasingly big example of this and there are many ecosystems in which you are prevented from running trusted software without great difficulty) and there are many general protections that are in OSes that will help you there.

On Linux you have some combination of Landlock, AppArmor, SELinux, calling prctl(PR_SET_NO_NEW_PRIVS), and the kitchen sink. On FreeBSD you have capsicum. Windows has integrity labeling + a bunch of stuff related to Job objects + a few things to disable win32k.sys calls.

But these are helpful and shouldn't be considered a panacea. The expectation is that you're delegating authority to a computer program to perform a certain task. Do computer programs abuse that authority sometimes? Absolutely. But nonetheless that's the fundamental model of most computer security, thanks in part to its usefulness.