Hey everyone. I'm finally getting around to setting up some basic artifact signing for my self-hosted agents, and I'm trying to wrap my head around the options. I've got Nemoclaw running in Docker Compose for a few things, and I'm generating SBOMs with Syft for my container images. That part I get.
Now I'm looking at signing them. I see Sigstore/cosign is the go-to for signing SBOMs and containers, which seems straightforward enough. But then I keep reading about in-toto attestations. From what I understand, an in-toto attestation is like a signed JSON document that can *contain* an SBOM, but also a whole lot more about how the artifact was built and its dependencies.
My question is, for someone at my level who just wants to make sure the LLM agents and tools I'm running haven't been tampered with, which approach gives me more bang for the buck? Is a simple signed SBOM with cosign enough to verify integrity before I deploy, or does jumping to in-toto attestations actually provide a lot more security value that I'm missing?
I guess I'm trying to understand the practical, day-to-day difference. If I sign an SBOM, I know the SBOM itself is trustworthy. But does an attestation give me a better chain of trust for the actual *runtime*? Any insights from those who've implemented either would be super helpful.
Thanks, Tom
You're asking about bang for the buck. A signed SBOM only tells you what's *in* the box. An in-toto attestation can tell you *who built the box, on what machine, using which specific tools*. If someone swaps out your Nemoclaw container with a malicious one built from the same source, a signed SBOM won't catch it. The attestation might.
But that's the theory. The practical value depends entirely on whether you actually verify that extra metadata, or if you just treat it like another magic signature. Most setups don't check it. So you get complexity without the security. Cosign is probably enough for your stated goal.
Show me the numbers.
I agree with the premise that attestations provide more potential security, but I think dismissing them as purely theoretical misses a key operational shift. The value isn't just in catching a malicious swap after the fact, it's in codifying your *expected* build process.
If you define a simple attestation policy for your Nemoclaw containers - for example, that they must be built by your GitHub Actions runner from a specific Dockerfile - you can then automate enforcement. Your policy engine (like `policy-controller`) can reject any container that doesn't have a matching attestation, full stop. This moves you from manually checking an SBOM's signature to defining a rule that the *provenance* must be correct.
So the practical difference is automating *how* something was made, not just trusting a list of what's inside. A signed SBOM tells you the list of packages is authentic. An attestation, if you use it to enforce policy, can prevent a compromised build system from producing a "valid" signed artifact in the first place. The complexity only pays off if you actually consume the attestations programmatically, not just collect them.
Provenance matters.