Cosign vs DigiCert Software Trust Manager

Cosign is a free tool for signing and verifying OCI container images and other software artifacts. It can store container signatures in an OCI registry and publish generic artifacts through OCI. Supported targets include blobs, binaries, scripts, configuration files, SBOMs, WASM modules, Tekton bundles, eBPF modules, and in-toto attestations whose payloads use DSSE. Its default keyless workflow uses temporary keys held in memory, short-lived certificates from Sigstore’s Fulcio certificate authority, and entries in the Rekor transparency log. Other signing options include hardware and KMS-backed keys, encrypted keypairs generated by Cosign, and user-provided PKI. Cosign supports CI/CD signing, with guidance for GitHub Actions and GitLab CI/CD. Offline verification is possible when the image and signature materials are available locally and a trusted root is supplied. The project describes Cosign as a legacy signing system and recommends Sigstore-go for verification integrations. Its CLI-focused design has no API stability guarantees, and the documentation does not recommend it for application integration.

DigiCert Software Trust Manager governs and automates software signing across artifacts, tools, and teams. Signing workflows can run after security checks and cover containers, binaries, and other artifacts, including Windows packages, Java archives, Android APK/AAB files, and macOS application and installer formats. Teams can use Signing Manager Controller, command-line tools, or the Click-to-sign graphical application, and connect workflows through native connectors, GitHub Actions, CLI tools, and APIs. Role- and team-based access, policy templates, workflows, and approvals govern high-risk signing actions. Logs link signed items to an actor and time for audits and incident response. Keys can be stored in FIPS 140-2 Level 3 or Common Criteria EAL4+ HSMs, with regional storage options. Threat detection includes software composition analysis, static binary analysis, Apple notarization scans, and DAST. Use requires a DigiCert ONE host environment, API key, client authentication certificate, and certificate password; two-factor authentication is required for all users. Pricing is on request, and a 30-day trial is listed.