Verify keyless signature

Verify keyless sig pinning the signer identity and OIDC issuer; note: pin both

cosign verify --certificate-identity=<id> --certificate-oidc-issuer=<host> <host>/<name> | jq .
tool
cosign5 commands
tags
cosignsecuritytroubleshootingci

More cosign commands

  • Attest CycloneDX SBOM
    cosign attest --key cosign.key --predicate sbom.json --type cyclonedx <host>/<name>@sha256:<id>

    Attach a signed CycloneDX SBOM attestation to an image digest

  • Verify attestation by type
    cosign verify-attestation --key cosign.pub --type cyclonedx <host>/<name> | jq -r '.payload' | base64 -d | jq .

    Verify attestation then decode the in-toto payload to inspect the predicate

  • Sign image by digest
    cosign sign --key cosign.key <host>/<name>@sha256:<id>

    Sign by immutable digest, not tag; note: signing a tag is racy and insecure

  • Keyless sign via OIDC
    COSIGN_EXPERIMENTAL=1 cosign sign <host>/<name>@sha256:<id>

    Keyless signing with Fulcio/Rekor via OIDC identity; modern: default in cosign v2

all 5 cosign commands