Any user process can append anything they want to your shell rc (.bashrc, .zshrc). In this case, they added a bash function for a fake sudo prompt. It then uses the password the user entered to run a malicious payload as root.
replyIf you're running a malicious user process with write (or read) access to your files, you are arguably already compromised.
replyThe freaking point is that basically anything worth running will have that amount of access, even Flatpaks. And you don't freaking know what's malicious before hand.
replyI think that depends on your point of view. I wouldn't run a program on my computer unless I were sure that it's not malicious. And if you mean that some program I already trust could be exploited, that's true even for the Linux kernel or any sandbox / security solution you would come up with. I'm not denying that there's always a risk, but there's nothing good in running arbitrary code that you can't trust.
replyExactly the point. You are already fully compromised, sudo adds no security.
replyIt’s not, but the grandparent does point out 1 major flaw with sudo being a typically command that goes through normal path discovery. It makes it easier to escalate from a compromised user account to a compromised root account, since the end user is likely to type the root password into a command that can be shadowed in their user space.
replyBecause it is trivial for unprivileged malware to phish the password and escalate to root. No production system should ever ship with sudo.
replyYou do realize you can do the exact same thing on macOS? Just alias sudo to whatever you want. BSD I assume you can do the same with doas.
replyNo desktop system is safe from your attack, unless you take specific precautions like chattr on the file or chmodding your home directory, but that can lead to weird breakage.
You basically don’t use sudo on macOS though. Maybe once in a blue moon
replyYou're making a big assumption about how other people use their computers. If you're running mostly desktop applications on Linux, you wouldn't use sudo much either. And if anything, I use sudoish-to-actual-rootlike on Windows more than on Linux, because more things are gated behind elevated privileges (some papered over by default UAC settings, but only when manipulated through built-in GUI tools) and there's nothing as simple as Distrobox and rootless Podman to set up isolated non-root environments.
replyNo popular Linux desktop, I would grant you. I use QubesOS and my own distro, stagex.
replyTIL. Thanks for your input into how sudo might not be super secure on systems already dribbling with malware.
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