GitHub Actions is the weakest link

Back when GitHub Actions first came out, I used commit hashes rather than tags in all my `uses:` lines. Some of my colleagues disagreed, saying that tags were secure enough. I eventually said, "Well, for well-known actions like actions/checkout, sure; if that one gets compromised it'll be all over the news within minutes." But for all the third-party actions, I kept commit hashes.

I feel rather vindicated now. There's still a small possibility of getting supply-chain attacked via a SHA collision, or a relatively much larger (though still small in absolute terms) possibility of getting supply-chain attacked via NPM dependencies of the action you're relying on.

But if you're not using a commit hash in your `uses:` lines, go switch to it now. And if you're just using major-version-only tags like `v5` then do it RIGHT now, before that action gets a compromised version uploaded with a `v5.2.3` tag.

Great writeup. Though combined with the lack of lockfiles for transitive actions, relying purely on static analysis is tough. Linter like zizmor are great, but they struggle with deep composite actions trees and runtime template injection.

I got frustrated with the lack of security to started working myself on an open-source runtime sandbox for GHA: https://github.com/electricapp/hasp

The first check was inspired by the trivy attack. hasp enforces SHA pinning AND checks that a comment (# v4.1.2) actaully resolves to its preceding SHA. That grew into a larger suite of checks.

Instead of just statically parsing YAML it hooks into the runner env itself. Some of its runtime checks mirror what zizmor already does including resolving upstream SHAs to canonical branches (no impostor commits) and traversing the transitive dependency tree. I have a PR up with a comparison document here (hasp vs. zizmor): https://github.com/electricapp/hasp/pull/13/changes#diff-aab...

Furthermore, it sandboxes itself to prevent sensitive exfiltration by acting as a token broker which injects the secret at runtime -- the GH token can only ever be used to call the GH API. It uses landlock, seccomp, and eBPF via Rust, so no docker. The token broker sandbox can also be used to wrap a generic executable giving hasp generic applicability beyond GHA context (i.e. agentic or other contexts, where token runtime injection seems quite in vogue)

I'm using this as a stopgap until GH rolls out some of the features on its roadmap. I'm moving torward treating the runner as a zero-trust or actively malicious environment, so this was my small contribution on that front.

Programming in YAML has always seemed crazy to me. Actions seem like a great place to create a simple mixed imperative/declarative scripting language (js extension or whatever) with a solid instrumented/observable/debuggable runtime and an OO API that can be run locally against mock infrastructure.

I apologize in advance for the plug. I've spent the last 5 years warning of the importance of not leaving CI locked in a black box platform and proprietary DSL. All the while going on a quest to reinvent CI as an open, programmable platform. Honestly it's still a work-in-progress: it turns out that reinvention is hard! But, if you want a glimpse of what CI can be when you shed 30 years of legacy, consider checking out Dagger (https://dagger.io).

Or, if you just want to talk about the future of CI with like-minded systems engineers, without committing to using a particular product, consider joining our Discord: https://discord.com/invite/dagger-io

Yup! Still haven't switched off of Github, but considering it at this point. If you're in my shoes, here's some tools we use that help:

- https://github.com/sethvargo/ratchet for pinning external Actions/Workflows to specific commit hashes

- https://www.warpbuild.com/ for much faster runners (also: runs-on/namespace/buildjet/blacksmith/depot/... take your pick)

- soon moving to Buildkite for orchestration of our CI jobs

I still just need a reasonable alternative for the "store our git repo, allow us to make and merge prs" part of things. Hopefully someone takes all the pieces that the Pierre team is publishing and makes this available soon. The Github UI and the `gh` cli are actually really nice and the existing alternative code storage tools are not great IMO.

This should really what LLM ought to bring in terms of security. Be able to break things faster considering it is now easier for the maintainers to fix them.

This has downsides of course, moving further into the "everything rot so fast these days" trope, but we will in a adversarial world where the threat is constantly evolving.

Tomorrow (today) the servers and repo won't be scanned by scripts anymore but by increasingly capable models with knowledge about more security issues than many searchers.

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Github actions is running like treacle now. Even when our company pays lots of money for cloud and private Github runners.

I know its the go-to punchbag but I think enabling Copilot reviews globally for a large proportion of Github was a bit hasty.

The security problems aside, if it continues this way, people won't be able to ship and deploy code from Github actions.

We might dare I say it, have to go back to self hosted Jenkins or Travis CI.

I just have a Spot instance we use for our builds. It's turned on via serverless, runs it's job with a timeout and exits.

Lately i don't use any managed services and life couldn't be any simpler.

This aligns nicely with today's/current GitHub Actions outage