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Comment by LockAndLol | Hacker News Reader

`curl | sudo bash` should never have become a thing in the first place. To me, it's the most "WTF?" mode of installing anything. Especially when the source is HTTP.

In what world is that secure?

Pity Qubes is so heavy, otherwise I'd be using it

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would you feel better if your Makefile looks like this:

    install:
        [ $(id -u) -ne 0 ] && echo 'please run sudo make install' || curl https//my.thing | /bin/sh

it goes back to what jve said - it's a matter of trust. how often do you blindly run 'sudo make install' w/o reading the entirety of the build script? all the time I bet - it's because you trust the source

No.

I think I have never run `sudo make install`. Things I install come from package managers. Docker or a VM is used to test other software.

And of course trust is important, but if I encounter things like `curl | bash`, my trust is lost.

What difference does it make if you run `make install` or `curl | bash`? In both cases, you are running code you have not audited yourself. Or are you the kind who inspects every Makefile and installer script before installing? If not, why is one better than the other?

Because at least with make install you can have some trust in the delivery method, ie encrypted git or whatever. If you use just plain http....

So wget https://example.com/installer.tar.gz; tar -xvzf installer.tar.gz; cd installer; make install is okay for you?

But curl https://example.com/installer.sh | bash is not? Why?

I'm fine with the second too as long as the host is trustworthy and it's always https. Most of the time it isn't.

Whether it's `sudo make install` or `curl | bash`, in both cases you have the opportunity to first inspect the code that will be executed.

You don't have the opportunity in the latter case.

https://www.idontplaydarts.com/2016/04/detecting-curl-pipe-b...

Sorry, I don't follow.

If I have a makefile, I can inspect it and see what it does.

If I have shell script (or indeed a makefile!) that calls `curl | bash`, I can inspect that shell script and see the URL that is used with curl, and then inspect the contents that the URL returns.

You can't see what comes from `curl | bash` before you actually pipe it to bash, click the link and read the article please.

OK, I see - in theory, an attacker in control of the backend could write a handler that could craft a bash script that writes different content when `curl | bash` is used.

TBH, while I take your point, I do think it's a little disingenuous of you to claim that "You don't have the opportunity" to inspect the script prior to executing it - you ordinarily will, but can't in the unlikely event of an attack like the article describes, which would require an attacker to be in full control of the web server.

Off the top of my head, this could be mitigated in a couple of ways:

1. Hash a known-good script and check the hash matches prior to executing (this does however mean that you need to update the hash every time the remote script is changed)

2. Use curl to download the remote script to a local file first, and provide the opportunity to inspect it prior to piping it into bash

> Off the top of my head, this could be mitigated in a couple of ways:

Or the third opportunity of not piping curl to bash and using a proper repository that has all these integrity and authenticity checks built-in.

Basically all makefiles you run into in the wild for mature projects allow you to install it with a prefix. e.g. into the home folder. No need to sudo anything if you do that.

This is an important point lost in the noise.

The problem is that cattle should apply only to containers, not hosts or VMs. Why? root. Which is also why Docker is a nonstarter for anyone who wants to use containers securely.

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