{
  "schema": "varexis-public-evidence-record/0.3",
  "generated_at_utc": "2026-10-16T13:36:43.315Z",
  "record_id": "VXI-EXT-PROCUREMENT-COSIGN-EXPECTED-IDENTITY-01-v1",
  "record_kind": "external_reference",
  "title": "Cosign verification: Expected signer and artifact",
  "system": "Sigstore Cosign",
  "evidence_family": "vendor_evidence_review",
  "index_status": "PUBLIC_SAFE_SOURCE_REVIEW",
  "evidence_state": "PRIMARY_DOCUMENTATION_REVIEW_ONLY",
  "canonical_question": "Does any valid Cosign signature establish the supplier artifact we intended to accept?",
  "near_questions": [
    "Which signer identity is expected?",
    "Which OIDC issuer is trusted?",
    "Does the signature bind the requested image digest?",
    "Were claim checks disabled?",
    "Does a valid key prove the intended supplier identity?",
    "Is this an image or a separate blob?",
    "Which bundle or signature was verified?",
    "Are identity patterns overly broad?",
    "Was the exact downloaded artifact checked?",
    "Does the signature assess software safety?",
    "What verification result should be retained?",
    "Can I save the artifact-acceptance boundary?"
  ],
  "supported_claims": [
    {
      "claim": "Identity-based verification checks the expected certificate identity and OIDC issuer. Container verification normally checks the signed image digest; disabling claim checks changes what is established. A cryptographically valid signature without the intended identity and artifact binding is insufficient for the buyer acceptance decision.",
      "reliance": "DOCUMENTED_CAPABILITY_ONLY"
    }
  ],
  "not_demonstrated_claims": [
    "Verified buyer configuration or effective access rights",
    "Independent execution, completeness or security testing",
    "Vendor certification, legal compliance or guaranteed suitability"
  ],
  "public_summary": "Identity-based verification checks the expected certificate identity and OIDC issuer. Container verification normally checks the signed image digest; disabling claim checks changes what is established. A cryptographically valid signature without the intended identity and artifact binding is insufficient for the buyer acceptance decision.",
  "related_record_ids": [],
  "source_review": {
    "source_type": "official_external_documentation",
    "source_title": "Cosign verifying signatures",
    "source_url": "https://docs.sigstore.dev/cosign/verifying/verify/",
    "checked_on": "2026-10-16",
    "candidate_record_id": "VXI-EXT-PROCUREMENT-COSIGN-EXPECTED-IDENTITY-01-v1",
    "candidate_record_sha256": "eb763083d1aaf4bf754faefb1b65a0a6c2c7fd6d522750490779afc6a489a11b",
    "method": "Primary documentation reviewed for the published bounded statement.",
    "deployment_tested_by_varexis": false,
    "revalidation": "The delivered snapshot preserves the review date shown. Recheck current primary documentation and deployment context before relying on present applicability; payment does not trigger fresh research."
  },
  "answer_policy": {
    "classification": "DOCUMENTED_WITH_DEPLOYMENT_BOUNDARY",
    "bounded_answer": "Identity-based verification checks the expected certificate identity and OIDC issuer. Container verification normally checks the signed image digest; disabling claim checks changes what is established. A cryptographically valid signature without the intended identity and artifact binding is insufficient for the buyer acceptance decision.",
    "required_buyer_context": "Artifact identity, expected signer, issuer, bundle and verification options. Effective configuration and dated operational evidence have not been inspected.",
    "missing_evidence": "A broader claim needs evidence matching the intended use. Payment does not upgrade the evidence state."
  },
  "private_boundary": "Raw logs, thresholds, private paths, source code, protected mechanisms and reconstruction-level details are excluded from public and paid delivery.",
  "decision_profile": {
    "schema": "varexis-vendor-evidence-review/1",
    "review_status": "documentation_review_only",
    "checked_on": "2026-10-16",
    "claim_to_check": "Any valid signature is enough to accept an artifact as the intended supplier release.",
    "documented_statement": {
      "status": "documented",
      "statement": "Identity-based verification checks the expected certificate identity and OIDC issuer. Container verification normally checks the signed image digest; disabling claim checks changes what is established. A cryptographically valid signature without the intended identity and artifact binding is insufficient for the buyer acceptance decision.",
      "source_ids": [
        "sigstore"
      ]
    },
    "buyer_evidence_required": [
      "Expected signer identity and issuer.",
      "Artifact digest and signed payload.",
      "Verification flags and policy result."
    ],
    "review_condition": {
      "status": "varexis_review_policy",
      "statement": "Require the intended signer and artifact binding; do not treat signature validity as a safety assessment."
    },
    "unknowns": "The buyer configuration, contract, effective entitlement and operational evidence have not been inspected. Missing evidence does not establish absence or failure of the feature.",
    "evidence_sources": [
      {
        "source_id": "sigstore",
        "url": "https://docs.sigstore.dev/cosign/verifying/verify/",
        "final_url": "https://docs.sigstore.dev/cosign/verifying/verify/",
        "title": "Cosign verifying signatures",
        "checked_on": "2026-10-16",
        "sha256": "cddc158241a16c414589b05f77674d24902660e61c722f9630414c16a753e298",
        "bytes": 73554
      }
    ],
    "observed_deployment": false,
    "commercial_reliance_boundary": "Procurement evidence support only; no supplier clearance, legal conclusion, configuration audit or verification of the buyer's claim is supplied.",
    "paid_value": {
      "decision_context": "Save the acceptance criteria and source version behind an artifact-origin review.",
      "free": "Complete review, practical questions, sources and limitations; may be saved locally.",
      "single_request": "Existing server-saved version-bound route snapshot for later authenticated retrieval.",
      "evidence_receipt": "The same snapshot plus the existing unsigned delivery receipt.",
      "excluded": [
        "Fresh vendor research",
        "Continuous monitoring or change alerts",
        "Testing the buyer configuration",
        "Private evidence or vendor certification"
      ],
      "integrity": "Hashes identify content versions; they do not prove truth or provide a signature."
    },
    "revalidation": {
      "trigger": "A saved purchase does not recheck the source or buyer configuration.",
      "specific_watch": "Artifact identity, expected signer, issuer, bundle and verification options."
    }
  },
  "paid_access_note": "The full published answer and boundaries are free. Paid access saves the selected route and source versions, with an unsigned receipt when purchased. Preview coverage before paying. Fresh research, bespoke assessment and protected evidence are excluded.",
  "service_route": {
    "request_guide": "/varexis-index/request.html",
    "request_workflow": "/varexis-index/request-workflow.json",
    "service_id": "single_request",
    "service_routes_url": "/varexis-index/service-routes.json",
    "payment_required": true,
    "availability_endpoint": "/api/index/capabilities",
    "operational_status": "AUTOMATIC_SERVICE_CAPABILITIES_GATED",
    "checkout_url": "/index-access"
  },
  "authority_boundary": "VAREXIS-INDEX informs evidence reliance. It does not provide advice, certification, deployment authority, security assurance, production approval, or guarantee.",
  "human_page": "/varexis-index/catalog.html#cosign-verification-expected-signer-digest",
  "machine_readable_record": "/varexis-index/records/cosign-verification-expected-signer-digest.json"
}