You could just read the script file first.. Or YOLO trust it like you trust any file downloaded from a relatively safe source.. At least you can read a script.
this post was submitted on 13 Mar 2025
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For security reasons, I review every line of code before it’s executed on my machine.
Before I die, I hope to take my ‘93 dell optiplex out of its box and finally see what this whole internet thing is about.
Not good enough. You should really be inspecting your CPU with a microscope.
It isn’t more dangerous than running a binary downloaded from them by any other means. It isn’t more dangerous than downloaded installer programs common with Windows.
TBH macOS has had the more secure idea of by default using sandboxes applications downloaded directly without any sort of installer. Linux is starting to head in that direction now with things like Flatpak.
If you're worried, download it into a file first and read it.
What's stopping the downloaded script from wiping my home directory?
What's stopping any Makefile, build script, or executable from running rm -rf ~? The correct answer is "nothing". PPAs are similarly open, things are a little safer if you only use your distro's default package sources, but it's always possible that a program will want to be able to delete something in your home directory, so it always has permission.
Containerized apps are the only way around this, where they get their own home directory.
Don't forget your package manager, running someone's installer as root
It's roughly the same state as when windows vista rolled out UAC in 2007 and everything still required admin rights because that's just how everything worked....but unlike Microsoft, Linux distros never did the thing of splitting off installs into admin vs unprivileged user installers.
plenty of package managers have.
flatpak doesn't require any admin to install a new app
nixos doesn't run any code at all on your machine for just adding a package assuming it's already been cached. if it hasn't been cached it's run in a sandbox. the cases other package managers use post install configuration scripts for are a different mechanism which possibly has root access depending on what it is.
And don't forget to sudo!
This is just normal Linux poor security. Even giants like docker do this.
Docker doesn't do this anymore. Their install script got moved to "only do this for testing".
Use a convenience script. Only recommended for testing and development environments.
Now, their install page recommends packages/repos first, and then a manual install of the binaries second.
Back up your data folks. You're probably more likely to accidentally rm -rf yourself than download a script that will do it.
To be fair that's because Linux funnels you to the safeguard-free terminal where it's much harder to visualize what's going on and fewer checks to make sure you're doing what you mean to be doing. I know it's been a trend for a long time where software devs think they are immune from mistakes but...they aren't. And nor is anyone else.
The security concerns are often overblown. The bigger problem for me is I don't know what kind of mess it's going to make or whether I can undo it. If it's a .deb or even a tarball to extract in /usr/local then I know how to uninstall.
I will still use them sometimes but for things I know and understand - e.g. rustup will put things in ~/.rustup and update the PATH in my shell profile and because I know that's what it does I'm happy to use the automation on a new system.
Damn that's bad misinformation. Its a security nightmare
So tell me: if I download and run a bash script over https, or a .deb file over https and then install it, why is the former a "security nightmare" and the latter not?
Both are a security nightmare, if you're not verifying the signature.
You should verify the signature of all things you download before running it. Be it a bash script or a .deb file or a .AppImage or to-be-compiled sourcecode.
Best thing is to just use your Repo's package manager. Apt will not run anything that isn't properly signed by a package team members release PGP key.
I have to assume that we're in this situation because because the app does not exist in our distro's repo (or homebrew or whatever else). So how do you go about this verification? You need a trusted public key, right? You wouldn't happen to be downloading that from the same website that you're worried might be sending you compromised scripts or binaries? You wouldn't happen to be downloading the key from a public keyserver and assuming it belongs to the person whose name is on it?
This is such a ridiculously high bar to avert a "security nightmare". Regular users will be better off ignoring such esoteric suggestions and just looking for lots of stars on GitHub.
No, you download the key from many distinct domains and verify it matches before TOFU
Ah yes, so straightforward.
For example: A compromised host could detect whether you are downloading the script or piping it.
I'm confident that if the host is compromised I'm screwed regardless.
No it isn't. What could a Bash script do that the executable it downloads couldn't do?
It's not just protection against security, but also human error.
https://github.com/MrMEEE/bumblebee-Old-and-abbandoned/issues/123
https://hackaday.com/2024/01/20/how-a-steam-bug-once-deleted-all-of-someones-user-data/
Just because I trust someone to write a program in a modern language they are familier in, doesn't mean I trust them to write an install script in bash, especially given how many footguns bash has.
Hilarious, but not a security issue. Just shitty Bash coding.
And I agree it's easier to make these mistakes in Bash, but I don't think anyone here is really making the argument that curl | bash is bad because Bash is a shitty error-prone language (it is).
Definitely the most valid point I've read in this thread though. I wish we had a viable alternative. Maybe the Linux community could work on that instead of moaning about it.
Hilarious, but not a security issue. Just shitty Bash coding.
It absolutely is a security issue. I had a little brain fart, but what I meant to say was "Security isn't just protection from malice, but also protection from mistakes".
Let's put it differently:
Hilarious, but not a security issue. Just shitty C coding.
This is a common sentiment people say about C, and I have a the same opinion about it. I would rather we use systems in place that don't give people the opportunity to make mistakes.
I wish we had a viable alternative. Maybe the Linux community could work on that instead of moaning about it.
Viable alternative for what? Packaging.
I personally quite like the systems we have. The "install anything from the internet" is exactly how Windows ends up with so much malware. The best way to package software for users is via a package manager, that not only puts more eyes on the software, but many package managers also have built in functionality that makes the process more reliable and secure. For example signatures create a chain of trust. I really like Nix as a distro-agnostic package manager, because due to the unique way they do things, it's impossible for one package's build process to interfere with another.
If you want to do "install anything from the internet" it's best to do it with containers and sandboxing. Docker/podman for services, and Flatpak for desktop apps, where it's pretty easy to publish to flathub. Both also seem to be pretty easy, and pretty popular — I commonly find niche things I look at ship a docker image.
You're telling me that you dont verify the signatures od the binaries you download before running them too?!? God help you.
I download my binaries with apt, which will refuse to install the binary if the signature doesn't match.
No because there's very little point. Checking signatures only makes sense if the signatures are distributed in a more secure channel than the actual software. Basically the only time that happens is when software is distributed via untrusted mirror services.
Most software I install via curl | bash is first-party hosted and signatures don't add any security.
All publishing infrastructure shouldn't be trusted. Theres countless historical examples of this.
Use crypto. It works.
By definition nothing
The point you appear to be making is "everything is insecure so nothing is" and the point others are making is "everything is insecure so everything is"
No, the point I am making is there are no additional security implications from executing a Bash script that someone sends you over executing a binary that they send you. I don't know how to make that clearer.
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