Red Hat Trusted Artifact Signer vs Sigstore

Red Hat Trusted Artifact Signer (RHTAS) helps organizations sign and verify software artifacts, including container images, binaries, documents, source-code commits, software bills of materials, build artifacts, and AI/ML models. Red Hat describes it as an enterprise deployment of Sigstore. Its client tools include cosign, gitsign, and rekor-cli. Signing can use OpenID Connect identities or self-managed keys held in a third-party key management system. A certificate transparency log records signing events in an immutable ledger that Red Hat says is inaccessible to the public. Deployment guidance covers Red Hat OpenShift Container Platform and Red Hat Enterprise Linux; Amazon EKS is listed as a development preview for RHTAS 1.4. The OpenShift guide requires version 4.16 or later, cluster-admin access, an OIDC provider, and the oc command-line tool. CLI binaries are listed for Windows, macOS, and Linux. Pricing is on request, and a 60-day trial is listed. Signing and verifying AI/ML models with the CLI is marked Technology Preview and is not covered by production SLAs.

Sigstore is a free, open source project for signing and verifying software artifacts to improve supply chain security. It supports release files, container images, binaries, software bills of materials, and more. Signatures use temporary keys, so developers do not have to manage signing keys; events are recorded in a tamper-resistant public log for audit. Its components include Cosign, Fulcio, Rekor, OpenID Connect, and Policy Controller. Cosign signs and verifies artifacts and stores signatures in an OCI registry. Fulcio issues temporary certificates to authorized identities, while Rekor keeps signed metadata in a searchable ledger. OpenID Connect authenticates users through providers such as GitHub and Google. The trust root uses The Update Framework and is maintained by five keyholders from different companies and academic institutions. Sigstore provides GitHub Actions, documents GitLab CI installation, and offers official clients for Go, Java, JavaScript, Python, Ruby, and Rust. It supports API, Linux, macOS, Windows, and self-hosted environments. One integration caveat is that Cosign has no API stability guarantees, does not follow semantic versioning, and is not recommended for application integration because of its dependencies.