{ "schema": "varexis-index-free-publication-preview/1", "catalogue_version": "pub-9-tranche-59-v1", "route_id": "agentic_reviewed_http_signature_replay_window_nonce", "record_id": "VXI-EXT-PROCUREMENT-HTTP-SIGNATURE-REPLAY-WINDOW-NONCE-01-v1", "question": "Does a valid HTTP message signature prove that this request has not already been used?", "answer": "RFC 9421 explains that a signature can remain valid when attached to another sufficiently similar message. Component coverage, a per-message nonce checked for repetition, and creation or expiry limits can help detect replay. The application must establish those controls; signature validity alone is not evidence of one execution or an idempotent business operation.", "records": [ { "record_id": "VXI-EXT-PROCUREMENT-HTTP-SIGNATURE-REPLAY-WINDOW-NONCE-01-v1", "url": "/varexis-index/records/http-signature-replay-window-nonce.json", "content_sha256": "cfed8d312970f5f85a1f0c998309a44d6c9330ad7e290ac039e826603b1a0322", "evidence": { "schema": "varexis-public-evidence-record/0.3", "generated_at_utc": "2026-10-25T20:55:19.974986+00:00", "record_id": "VXI-EXT-PROCUREMENT-HTTP-SIGNATURE-REPLAY-WINDOW-NONCE-01-v1", "record_kind": "external_reference", "title": "HTTP signature replay controls", "system": "IETF RFC 9421", "evidence_family": "vendor_evidence_review", "index_status": "PUBLIC_SAFE_SOURCE_REVIEW", "evidence_state": "PRIMARY_DOCUMENTATION_REVIEW_ONLY", "canonical_question": "Does a valid HTTP message signature prove that this request has not already been used?", "near_questions": [ "Can the same valid HTTP signature be replayed?", "What does a repeated HTTP signature nonce indicate?", "Does a signature creation time prove a request was used once?", "Can HTTP signature verification replace business idempotency?" ], "supported_claims": [ { "claim": "RFC 9421 explains that a signature can remain valid when attached to another sufficiently similar message. Component coverage, a per-message nonce checked for repetition, and creation or expiry limits can help detect replay. The application must establish those controls; signature validity alone is not evidence of one execution or an idempotent business operation.", "reliance": "DOCUMENTED_CAPABILITY_ONLY" } ], "not_demonstrated_claims": [ "Require the application replay policy, nonce uniqueness and time-window checks; a timestamp alone is not exactly-once execution.", "Buyer implementation, live runtime enforcement, settled payment, physical outcome, certification or permission to act are not established.", "No expanded capabilities or licences for existing INDEX executables." ], "public_summary": "RFC 9421 explains that a signature can remain valid when attached to another sufficiently similar message. Component coverage, a per-message nonce checked for repetition, and creation or expiry limits can help detect replay. The application must establish those controls; signature validity alone is not evidence of one execution or an idempotent business operation.", "related_record_ids": [], "source_review": { "source_type": "official_external_documentation", "source_title": "IETF RFC 9421", "source_url": "https://www.rfc-editor.org/rfc/rfc9421.txt", "checked_on": "2026-10-25", "candidate_record_id": "VXI-EXT-PROCUREMENT-HTTP-SIGNATURE-REPLAY-WINDOW-NONCE-01-v1", "candidate_record_sha256": "d9e8cec0b0e91fd3add9370197f0483be92d9fb56f71cea92903873860343d25", "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": "RFC 9421 explains that a signature can remain valid when attached to another sufficiently similar message. Component coverage, a per-message nonce checked for repetition, and creation or expiry limits can help detect replay. The application must establish those controls; signature validity alone is not evidence of one execution or an idempotent business operation.", "required_buyer_context": "Covered components and message identity; Nonce uniqueness state; Creation/expiry acceptance policy. Buyer deployment not 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": "2026-10-25", "claim_to_check": "Does a valid HTTP message signature prove that this request has not already been used?", "documented_statement": { "status": "documented", "statement": "RFC 9421 explains that a signature can remain valid when attached to another sufficiently similar message. Component coverage, a per-message nonce checked for repetition, and creation or expiry limits can help detect replay. The application must establish those controls; signature validity alone is not evidence of one execution or an idempotent business operation.", "source_ids": [ "rfc9421" ] }, "review_inference": { "status": "review_inference", "statement": "Distinguish a valid HTTP signature from evidence that the request has not been replayed. This is a documentation-review judgment, not an observed deployment outcome.", "source_ids": [ "rfc9421" ] }, "buyer_evidence_required": [ "Covered components and message identity", "Nonce uniqueness state", "Creation/expiry acceptance policy" ], "review_condition": { "status": "varexis_review_policy", "statement": "Refuse buyer-specific assurance from documentation alone. Require the application replay policy, nonce uniqueness and time-window checks; a timestamp alone is not exactly-once execution." }, "unknowns": "The buyer implementation, effective configuration, complete evidence inventory and actual business outcome were not inspected.", "unknown_finding": { "status": "unknown", "statement": "The buyer implementation, effective configuration, complete evidence inventory and actual business outcome were not inspected." }, "evidence_sources": [ { "source_id": "rfc9421", "url": "https://www.rfc-editor.org/rfc/rfc9421.txt", "final_url": "https://www.rfc-editor.org/rfc/rfc9421.txt", "status": 200, "captured_at_utc": "2026-10-25T20:26:12.767Z", "sha256": "612655786bf4293bfc486e4177571467fbb3de6e6f0eea90cb74c346a34fdf3c", "bytes": 241160, "title": "IETF RFC 9421", "hash_basis": "SHA-256 of unmodified HTTP response body bytes", "rights_review": "Original factual paraphrase of the cited IETF RFC; IETF Trust and contributor rights remain applicable. No RFC text, code component or modified standard is redistributed.", "checked_on": "2026-10-25", "capture_status": 200, "claim_review_completed": true, "reviewed_sections": [ "3.2.1", "7.2.1", "7.2.2", "2.4", "7.2.5", "7.2.6", "7.3.4", "7.2.8", "7.4.3" ], "version_context": "Fixed IETF RFC 9421 publication; later applicable updates and actual implementation conformance require separate review." } ], "observed_deployment": false, "commercial_reliance_boundary": "Documentation review only; the buyer must establish applicability and actual outcomes. INDEX does not inspect or control the deployment.", "paid_value": { "decision_context": "Distinguish a valid HTTP signature from evidence that the request has not been replayed.", "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": "Recheck 7.2.2 in IETF RFC 9421 when the source, applicable version, configuration or intended reliance changes. A detected change creates a review candidate, not automatic approval." }, "buyer_relevance": "Distinguish a valid HTTP signature from evidence that the request has not been replayed.", "refusal_conditions": [ "Refuse buyer-specific assurance from documentation alone. Require the application replay policy, nonce uniqueness and time-window checks; a timestamp alone is not exactly-once execution." ] }, "niche": { "niche_id": "agent-authority-action-evidence", "label": "Agent Authority & Action Evidence", "classification_id": "audit", "classification_label": "Audit, Provenance & Evidence Accountability", "topic_id": "audit", "buyer_intent": "Distinguish a valid HTTP signature from evidence that the request has not been replayed.", "comparison_role": "supplementary_discovery" }, "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#http-signature-replay-window-nonce", "machine_readable_record": "/varexis-index/records/http-signature-replay-window-nonce.json" } } ], "access": { "mode": "exact_http_only", "payment_required": false, "purchase_url": null, "mcp_preview_available": false, "paid_saved_retrieval_available": false, "natural_language_search_qualified": false }, "boundary": "Catalogue additions are available free through the exact HTTP JSON links below. Enhanced natural-language discovery is not yet qualified for these records. They are outside MCP search, MCP preview and paid saved retrieval. No search qualification, executable capability or entitlement is added.", "content_sha256": "b5b09971c3db37de181e69d18dce6da80f489d22a70dcaa2b8190636fef1d2cb" }