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curl https://some-url | sh

I see this all over the place nowadays, even in communities that, I would think, should be security conscious. How is that safe? What's stopping the downloaded script from wiping my home directory? If you use this, how can you feel comfortable?

I understand that we have the same problems with the installed application, even if it was downloaded and installed manually. But I feel the bar for making a mistake in a shell script is much lower than in whatever language the main application is written. Don't we have something better than "sh" for this? Something with less power to do harm?

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[-] emberpunk@lemmy.ml 2 points 3 hours ago

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.

[-] Zron@lemmy.world 9 points 7 hours ago

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.

[-] moseschrute@lemmy.ml 4 points 4 hours ago* (last edited 4 hours ago)

Not good enough. You should really be inspecting your CPU with a microscope.

[-] moonpiedumplings@programming.dev 6 points 7 hours ago

What's stopping the downloaded script from wiping my home directory?

Lol. Lmao

[-] WolfLink@sh.itjust.works 10 points 10 hours ago* (last edited 10 hours ago)

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.

[-] ExperimentalGuy@programming.dev 13 points 15 hours ago

If you're worried, download it into a file first and read it.

[-] Artyom@lemm.ee 36 points 20 hours ago

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.

[-] easily3667@lemmus.org 4 points 12 hours ago* (last edited 12 hours ago)

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.

[-] brian@programming.dev 2 points 6 hours ago

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.

[-] Boomkop3@reddthat.com 4 points 15 hours ago

And don't forget to sudo!

[-] easily3667@lemmus.org 9 points 20 hours ago

This is just normal Linux poor security. Even giants like docker do this.

[-] moonpiedumplings@programming.dev 1 points 7 hours ago

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.

[-] tatterdemalion@programming.dev 6 points 21 hours ago

Back up your data folks. You're probably more likely to accidentally rm -rf yourself than download a script that will do it.

[-] easily3667@lemmus.org 1 points 12 hours ago* (last edited 12 hours ago)

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.

[-] thomask@lemmy.sdf.org 13 points 1 day ago* (last edited 1 day ago)

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.

[-] jagged_circle@feddit.nl 6 points 23 hours ago

Damn that's bad misinformation. Its a security nightmare

[-] thomask@lemmy.sdf.org 10 points 22 hours ago* (last edited 22 hours ago)

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?

[-] jagged_circle@feddit.nl 2 points 11 hours ago

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.

[-] thomask@lemmy.sdf.org 0 points 3 hours ago

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.

[-] jagged_circle@feddit.nl 1 points 11 minutes ago

No, you download the key from many distinct domains and verify it matches before TOFU

[-] rocky_patriot@programming.dev 2 points 12 hours ago

For example: A compromised host could detect whether you are downloading the script or piping it.

[-] thomask@lemmy.sdf.org 1 points 3 hours ago

I'm confident that if the host is compromised I'm screwed regardless.

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[-] jagged_circle@feddit.nl 6 points 23 hours ago* (last edited 23 hours ago)

I dont just cringe, I open a bug report. You can be the change to fix this.

[-] Scrollone@feddit.it 2 points 7 hours ago

Can we also open bug reports for open-source projects that base their community on Discord?

[-] jagged_circle@feddit.nl 1 points 9 minutes ago
[-] Akito@lemmy.zip 3 points 12 hours ago

One of the few worthwhile comments on Lemmy...

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this post was submitted on 13 Mar 2025
267 points (96.5% liked)

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