{"slug":"api-zfinia-com-x402-v1-email-header-authentication-audit-089bb0","title":"Read the authentication headers a receiver added to one message","host":"api.zfinia.com","method":"POST","resource":"https://api.zfinia.com/x402/v1/email-header-authentication-audit","category":"code","description":"Read the authentication headers a receiver added to one message. Headers are unfolded first, because a field continues on any line beginning with whitespace. Reports two From headers, where what is displayed and what is evaluated can differ, which is the shape of a spoof rather than a mistake; a low","price_listed":0.2,"price_asked":null,"state":"down","state_label":"Not answering","checks_7d":1,"answered_7d":0,"latency_ms_median":null,"reported_calls_30d":1,"reported_payers_30d":1,"networks":["eip155:8453"],"badge":"unverified","paid_checks_7d":0,"paid_ok_7d":0,"example_input":{"body":{"expected_from_domain":"example.test","headers":"Received: from relay.vendor.test (relay.vendor.test [198.51.100.7])\n\tby mx.receiver.test with ESMTPS id abc123\n\tfor <ada@receiver.test>; Thu, 2 Oct 2026 12:00:00 +0000\nAuthentication-Results: relay.vendor.test;\n\tspf=softfail smtp.mailfrom=bounces.vendor.test;\n\tdkim=pass header.d=vendor.test;\n\tdmarc=fail\nAuthentication-Results: mx.receiver.test; spf=pass smtp.mailfrom=example.test; dkim=pass header.d=example.test\nFrom: Billing <billing@example.test>\nFrom: Billing <billing@example-test.test>\nSubject: Your invoice\n","trusted_authserv_ids":["mx.receiver.test"]},"bodyType":"json","method":"POST","type":"http"},"output_schema":{"$schema":"https://json-schema.org/draft/2020-12/schema","properties":{"input":{"additionalProperties":false,"properties":{"body":{"additionalProperties":false,"properties":{"expected_from_domain":{"maxLength":253,"type":"string"},"headers":{"maxLength":131072,"type":"string"},"trusted_authserv_ids":{"items":{"maxLength":253,"type":"string"},"maxItems":50,"minItems":1,"type":"array"}},"required":["headers"],"type":"object"},"bodyType":{"enum":["json","form-data","text"],"type":"string"},"method":{"enum":["POST"],"type":"string"},"type":{"const":"http","type":"string"}},"required":["type","method","bodyType","body"],"type":"object"},"output":{"properties":{"example":{"type":"object"},"type":{"type":"string"}},"required":["type"],"type":"object"}},"required":["input"],"type":"object"},"history":[{"day":"2026-10-04","reachable":false,"status":null,"valid_402":false,"asked_usdc":null,"price_match":null,"latency_ms":null,"error":"TimeoutError"}],"description_full":"Read the authentication headers a receiver added to one message. Headers are unfolded first, because a field continues on any line beginning with whitespace. Reports two From headers, where what is displayed and what is evaluated can differ, which is the shape of a spoof rather than a mistake; a lower Authentication-Results, which can have been written before the message arrived; a result from an untrusted server; and a DKIM or SPF domain that does not align with the From domain.","last_updated":"2026-10-04T08:41:09.696Z","schemes":["exact"]}