Financial API Security Testing: Open Banking, PSD2, and Payment Integrations — 日本企業向けガイド

Financial APIs — open banking interfaces, payment processing APIs, financial data aggregation endpoints — handle the most sensitive operations: money movement and financial data access. Security testing covers: strong customer authentication implementation, consent management and scope enforcement, transaction integrity (can amounts, recipients, or currencies be manipulated?), API versioning and deprecation security, rate limiting against financial fraud automation, certificate-based authentication (eIDAS, mTLS), and regulatory compliance (PSD2, open banking standards). Financial API vulnerabilities have direct monetary impact — making this testing particularly high-value.