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Comment by no-name-here | Hacker News Reader

> You have to review the source of every PKGBUILD from the AUR you install, full stop. Yes that includes any updates.

But isn’t that also the case for every browser extension, VSCode extension, nuget package, Cargo crate, python package, npm package, etc? (Unless you are running them somewhere without internet access or without access to anything you don’t mind being public?)

Maybe it’s not the case for aur, but the others could theoretically be improved with better permissions, sandboxing, etc. I guess browser extensions basically have those options, even if no “normal” users use them.

Unfortunately 99.99% of people can’t or don’t have the time to review everything. :-(

I guess distro packages where there are trusted maintainers, or places like the iOS App Store where there are both permissions and somewhat of a review process, are the safest.

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> isn’t that also the case for every browser extension, VSCode extension, nuget package, Cargo crate, python package, npm package

Yes, and all of those have supply chain hacks in them, and have happened within the last year? In this specific case, it's a malicious npm package being installed with official npm tooling in the PKGBUILD.

The advantage to the AUR is just that you can reasonably review every PKGBUILD for what you're installing, they are very simple bash scripts. It'd be great if more people would donate resources to help verify and validate AUR scripts, but the AUR specifically exists for packages that the trusted users and devs of arch don't have time to personally maintain.

Curious, in this specific case: if people DID review the PKGBUILD, what exactly would they recognize to spot these packages were compromised ?

Some things I try to check for

- sources array has sources that don't correlate to the package name/purpose or are from strange places, like github repos that don't seem relevant etc.

- extensive post install scripts suggesting it's doing a lot more than is normal

But those are very crude, I wonder if an AUR helper could optionally consult a local LLM to review a PKGBUILD before installing these days...

> like github repos that don't seem relevant

i wouldn't necessarily trust a repo that does seem relevant either. it's trivial to put any data you want at a url which, at a glance, appears to legitimately belong to any repo you can fork.

typically attacks happen when the URL for the source code or binary gets changed significantly... or like in this attack someone adds something to the post_install section which does something like add an npm install command. a lot of updates for binaries are just version bumps and SHA hashes changing which are easy to vet if you trust the source to not be compromised.

From the concrete example someone posted below, you'd see that a post-install hook exists, literally this line:

> install=toggldesktop-bin-deps.install

And the toggldesktop-bin-deps.install contains this:

> post_install() {{

> cd /tmp

> bun add axios uuid ora js-digest

> }}

Seeing any install hook download anything from the web should immediately raise alarms when reviewing, even before you checkout what packages it actually installs.

Exactly, these hacks really stand out to me, and used odd patterns (like .install files that just had 2-3 line post_install functions) etc.

> The advantage to the AUR is just that you can reasonably review every PKGBUILD for what you're installing

Simply reviewing the PKGBUILD is not enough for the same reason reviewing a Makefile is not enough: You need to review the source code for _everything_ that is being downloaded and executed on your machine. For AUR packages, that means not just the PKGBUILD but the full source code for the program it is building and the full source code for any of its dependencies.

Hypothetical example: you wouldn't have caught the xzutils exploit by reading the PKGBUILD.

Right, the PKGBUILD only helps you review if you're installing what you intend to - not verifying if what you're installing contains any hacks.

This hack in particular added random npm packages that would have been unneeded/unintentional, and was visible in the PKGBUILDs directly.

True, but looking at a compromised PKGBUILD[0], it looks like it is installing "atomic-lockfile" and "figures". I think 99% of people reading the PKGBUILD would assume those are legit dependencies needed by the program. It's not like it was running "npm install 1337hax0r". Which is why you need to read the source for both "atomic-lockfile" and "figures" (and literally everything else).

[0] https://aur.archlinux.org/cgit/aur.git/commit/?h=pass-cli&id...

It adds npm as a dependency, to a go build?

It changes the contributor email?

to install random npm packages?!

in /tmp?! in post_install()??! With a new random contributor email????

Archlinux is focused on enabling a specific type of user, and certainly ones that can read bash scripts, and understand reasonable depedencies vs unreasonable ones. And even then - this is specifically in the AUR and not a package the distro directly offers.

> It adds npm as a dependency, to a go build?

Programs often invoke other programs through the exec* family of syscalls. For example, git is written in C but it ships with perl dependencies. It is not unreasonable to assume pass-cli added a runtime dependency on a program written in javascript. Regardless, we're talking hundreds of AUR packages have been compromised, I'd be shocked if none of them were javascript-based programs. Perhaps pass-cli was simply a bad example for me to choose.

> It changes the contributor email?

I think this is the 2nd most sus change, but even so, I have changed email addresses over the years so it isn't completely unreasonable.

> in /tmp?!

And yes, this is the most sus change.

I'm not sure if you're trying to strawman or are inexperienced.

No, this in no way or shape looks like installing a legitimate dependency to the target audience (expert users). This is a package manager, you don't install dependencies via post_install.

No it wasn't? It ran npm install from post install script in another file. If they named it better people probably wouldn't have even noticed so quickly.

if someone setup a properly vetted LLM farm to donate local LLM resources, id give it ~8 hours a day on whatever model i have loaded.

Some of these have corporate backing and/or better funding and thus more manpower to review things, but yeah it essentially applies to all of them. It's no accident that there's news about a new npm package being compromised every other week.

Ultimately, the way we're doing permissions on the OS level is fundamentally broken on desktop OSes, and we're increasingly feeling the effects of that. Ideally everything should be sandboxed by default, and only given access to it's own files, instead of everything the user has.

But we're a long way away from that, and that's not something a single project could enforce.

Apparently I was almost affected, but I dont update arch frequently enough, that my alvr package was not updated during the window.

It's also a good thing that Arch Linux has people hawking it, so if these things happen they get caught on insanely quickly. I wonder if there's sane ways to protect your dotfiles from rogue processes just touching them.

I normally exclude all AUR packages from system updates to speed things up, so I shouldn't be affected either.

I usually use "yay" for all my stuff, so I might have to consider telling yay to only update system files, apparently one way to decrease this type of attack is to get a hardware key for your SSH files, might finally have a reason to get a yubikey or similar.

Yes, use a distro with good security posture such as Debian to reduce risk.

Are the packages in the repositories of arch also affected?

No? Then it's not a problem.

Every device in this household that isn't a smartphone runs on Arch.

All my servers run on Arch.

Never had a problem, because I don't blindly install stuff from the AUR.

I guess official arch packages are also ok nowadays, my point was more that one should avoid non-curated repositories of packages such as cargo.

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