Definition. Provenance, according to the SLSA specification, is verifiable information about where, when and how a software artifact was produced: which build platform built it, from which inputs and with which parameters. Technically it is a signed attestation in the in-toto format that refers to the artifact.

Why it matters. A signature proves who built something. Whether the artifact comes from the source you trust only becomes clear when the details in the provenance are compared against expected values, such as the correct source repository. The SLSA specification therefore explicitly expects verifiers to know what good provenance looks like.

Example. In the attack on LiteLLM 1.107.0 in October 2026, the container image was properly signed. Its provenance, however, named the fork Berri-AI/litellm as the source instead of BerriAI/litellm. A check of the source repository would have rejected the image.

Related. SLSA, SBOM, Supply chain attack