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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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[-] moonpiedumplings@programming.dev 3 points 20 minutes ago

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

Lol. Lmao

[-] Zron@lemmy.world 1 points 4 minutes 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.

[-] WolfLink@sh.itjust.works 5 points 3 hours ago* (last edited 3 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 10 points 8 hours ago

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

[-] Boomkop3@reddthat.com 3 points 7 hours ago

And don't forget to sudo!

[-] Artyom@lemm.ee 24 points 13 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 3 points 5 hours ago* (last edited 5 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.

[-] easily3667@lemmus.org 8 points 13 hours ago

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

[-] moonpiedumplings@programming.dev 1 points 26 minutes 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.

[-] ulterno@programming.dev -1 points 6 hours ago

I don't cringe. Just instinctively Ctrl+W

[-] tatterdemalion@programming.dev 6 points 14 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 5 hours ago* (last edited 5 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 12 points 19 hours ago* (last edited 19 hours 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 5 points 16 hours ago

Damn that's bad misinformation. Its a security nightmare

[-] thomask@lemmy.sdf.org 10 points 15 hours ago* (last edited 15 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 4 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.

[-] rocky_patriot@programming.dev 2 points 5 hours ago

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

[-] FizzyOrange@programming.dev 0 points 6 hours ago

No it isn't. What could a Bash script do that the executable it downloads couldn't do?

[-] moonpiedumplings@programming.dev 2 points 36 minutes ago

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.

[-] jagged_circle@feddit.nl 2 points 4 hours ago* (last edited 4 hours ago)

You're telling me that you dont verify the signatures of 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.

[-] easily3667@lemmus.org 1 points 5 hours ago* (last edited 5 hours ago)

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"

[-] jagged_circle@feddit.nl 5 points 16 hours ago* (last edited 16 hours ago)

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

[-] Scrollone@feddit.it 1 points 9 minutes ago

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

[-] Akito@lemmy.zip 2 points 4 hours ago

One of the few worthwhile comments on Lemmy...

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this post was submitted on 13 Mar 2025
248 points (96.6% liked)

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