> Target: Python package managers using tokio-tar (e.g., uv). An attacker uploads a malicious package to PyPI. The package's outer TAR contains a legitimate pyproject.toml, but the hidden inner TAR contains a malicious one that hijacks the build backend. During package installation, the malicious config overwrites the legitimate one, leading to RCE on developer machines and CI systems.

It seems to imply that you’re already installing a package uploaded by a malicious entity. Is the vulnerable workflow something like “you manually download the package archive, unpack it with system tar, audit all the files and then run uv install, which will see different files”?

That’s not to say oss cannot be trusted, but it certainly makes trusting smaller projects and packages scary.

I suspect there are other reasons too. There is a cost to fad languages being used. Replicating the ecosystem of libraries around a language is a huge job. Its rare that a language ever gets the same size and quality ecosystem as say C or Java. But the fans of the language will try. This leads to a lot of ported projects and a small number of devs maintaining a huge number of projects. That's a recipe for abandonware. I suspect a lot of student projects too which is also likely to do the same.

Languages where importing a library is hard, libraries tend to grow quite large. Large libraries have larger backing, more established development and security protocols. When OpenCV, TinyUSB, Numpy, nimBLE start to struggle, it's easier to notice and companies relying on them may step up to fork, maintain of fund its continued use.

Languages where importing and creating a library is easy, we see small atomic packages for small utility programs, over large libraries. This spreads the software supply-chain wider, into smaller teams of maintainers. If the same amount of code is fractured over 50 small libraries maintained by 1-3 people each, the likelihood of one or two becoming abandoned grows.

I've been a bit weary about the dependency and package manager approach more modern languages use. It trades convenience for some pretty scary supply-chain attacks.

1. easy to create

2. easy to produce something with decent quality

3. rust is widely used by a lot of people, including juniors which don't know (yet) that it can be quite a pain to maintain a package and that it comes with some responsibility

4. so small hobby projects now can very easily become widely used dependencies as people looked at them and found them to have decent quality

5. currently "flat" package structure (i.e. no prefixes/grouping by org/project) there has been discussions for improving on it for a long time but it's not quite here yet. This matters as e.g. all "official" tokio packages are named tokio-* but thats also true for most 3rd party packages "specifically made for tokio". So `tokio-tar` is what you would expect the official "tokio" tar package to be named _if there where one_.

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now the core problem of many unmaintained packages isn't that rust specific

it's just that rust is currently a common go to for young developers not yet burned by maintaining a package, it's supper easy to publish

on the other hand some of the previous "popular early carrier go to languages" had either not had a single "official" repo (Jave) or packaging was/is a quite a pain (python). Through you can find a lot of unmaintained packages in npm too, just it's so much easier to write clean decent looking code in rust that it's more likely that you use one in rust then in JS.

(Think about the last time you checked whether the stack of GNU libraries on your Linux desktop were actively maintained. I don’t think anybody thinks about it too hard, because the ecosystem discourages thinking about it!)

2. Completely FOSS, barely any salaried devs, if any they are donation based.

3. Culture for code "reuse" instead of actually coding. Everyone wants it in their own flavour (we have tar, but I kinda want async-oop-tar)

4. Cognitive dissonance between 3 and 1, rusties don't want to succumb and use a standard tar library because of performance (self inflicted performance hit from creating an incompatible ecosystem) or pride (we need a version written in rust). All of this to download software that is probably written in C and from another ecosystem anyways. (An encoding/compression is a signature and tarballs are signature CLinux)

Something's gotta give

If you build things with wires, diodes, multiplexers, breakers, fuses and keyed connectors there's less maintenance needed than if you try and build a system entirely out of transistors and manually applied insulators.

I haven't looked at the package itself, but was it built on top of the C libraries with like, bindgen?

e: a glance suggests thats not the case, but perhaps they were ported naively by simply cloning the structure without looking at what it was implementing? that's definitely the path of least resistance for this type of thing. On top of that the spec itself is apparently in POSIX, some parts of which are, well, spotty; compared to RFCs

Rust's advantage is that it can prevent logic errors from becoming memory safety vulnerabilities (and separately, its type system makes some - but not all - classes of logic errors more difficult to introduce).

But to your point: yes, it's a good example about how security bugs live at all layers of the stack and that being checked against memory corruption does nothing to prevent you from writing bugs in the semantic space.

My understanding is that the left-pad incident is not directly analogous, since it involved restoring a deleted package rather than modifying an extant package.

It'd be like putting zip in zip