An open-source stack for signing, verifying, and transparency-logging artifacts.
Sigstore is an open-source project under the Open Source Security Foundation (OpenSSF) that gives every software producer a free, automated way to sign their artifacts — containers, binaries, attestations, SBOMs — and every consumer a way to verify those signatures against a public transparency log. It removes the single biggest historical obstacle to ubiquitous signing: long-lived private keys.
In practice, Sigstore is three cooperating services plus a client: Fulcio issues short-lived certificates tied to an OIDC identity, Rekor appends every signing event to a tamper-evident transparency log, and Cosign is the command-line client that producers and verifiers actually run.
The keyless flow is the canonical Sigstore experience:
For thirty years, code signing was the default security control nobody used — because managing private keys across thousands of CI pipelines was operationally impossible. Sigstore replaces key management with identity management, and CI systems already know how to do identity. The result: signing is now free, automatic, and verifiable, which is the precondition for treating unsigned artifacts as suspicious by default.
Every major standard coming out of SLSA, CRA, and the US executive order on software supply chain security assumes the existence of something like Sigstore. In 2026, it is essentially the default answer.
No long-lived signing keys to rotate, revoke, or lose — identity is the key, and it lives in your existing OIDC provider.
Rekor gives you an independently verifiable log of every signing event, which regulators and customers can inspect without trusting your internal records.
GitHub Actions, GitLab, Buildkite, and most modern CI runners already speak OIDC — Sigstore signing is a one-line addition, not a new subsystem.
SLSA levels 2–3, the EU Cyber Resilience Act, and US M-22-18 attestation requirements all assume signed, logged artifacts — Sigstore is the default way to produce them.
Kubernetes, Node.js, PyPI, npm, and most major base-image providers now publish Sigstore signatures — which means verification is a meaningful policy, not a theoretical one.
Safeguard reads Sigstore signatures and Rekor entries as part of its component provenance graph — so the same engine that runs reachability also knows whether the artifact you are about to ship was signed by a recognised identity. That signal feeds policy gates, and it feeds zero-day discovery when an unsigned build appears where one never should.
Connect your registries. See which artifacts are signed, which aren't, and which identity signed them.