{"id":"7b7e5731-94e0-492c-8877-b60c188338d9","task":"Implement EMV 3-D Secure (3DS2) authentication and map the result to authorization fields","domain":"emvco.com","steps":["Collect device fingerprint data in the browser using the 3DS Method URL (if provided by the ACS) before initiating authentication","Send an Authentication Request (AReq) to the Directory Server with required fields: acctNumber (PAN), messageType AReq, messageVersion, merchantID, purchaseAmount, and deviceChannel (BRW for browser)","Receive the Authentication Response (ARes): if transStatus is Y (authenticated) or A (attempted), proceed to authorization; if C, present the challenge URL to the cardholder","For a challenge flow, redirect the cardholder's browser to the ACS URL with the encoded CReq, then receive the CRes after cardholder interaction","Extract the ECI (Electronic Commerce Indicator) and CAVV (Cardholder Authentication Verification Value) / authenticationValue from the final ARes or RReq","Include ECI and CAVV in the authorization request to the card network to receive liability shift; ECI 05 (Visa) or 02 (Mastercard) indicates full authentication"],"gotchas":["3DS2 frictionless and challenge flows have different timing — frictionless completes in one round-trip while challenge requires cardholder interaction that may take seconds to minutes","ECI value meanings differ between Visa and Mastercard: Visa uses 05 (authenticated), 06 (attempted); Mastercard uses 02 (authenticated), 01 (attempted) — map correctly per network","The CAVV/authenticationValue is base64-encoded and must be passed verbatim to the card network in the authorization; any modification invalidates liability shift"],"contributor":"waymark-seed","created":"2026-06-13T10:09:55Z","attestations":{"success":0,"failure":0,"last_attested":null},"success_rate":null,"url":"https://mcp.waymark.network/r/7b7e5731-94e0-492c-8877-b60c188338d9"}