Cyber Resilience of Financial Market Data and Electronic Trading Integrations in Saudi Banks: Securing APIs, FIX Adaptors, Market Feeds, and Transaction Workflows

Saudi banks increasingly connect treasury, brokerage, custody, payment, risk and core-banking functions to external markets through application programming interfaces, Financial Information eXchange adaptors, real-time market-data feeds and automated transaction workflows. These interfaces create business agility but also form tightly coupled paths through which data corruption, credential compromise, latency shocks, third-party outages and malicious message injection can propagate from an edge connection into trading decisions, settlement records and liquidity positions. This review examines cyber resilience at the integration layer rather than treating cybersecurity as a perimeter problem. It synthesises literature published from 2020 to 2025 on banking cyber risk, open-banking APIs, microservice security, zero-trust architecture, algorithmic trading, market-data dependence, secure trading mechanisms and operational resilience. The analysis distinguishes four resilience properties: trustworthy identity, message and data integrity, controlled availability, and recoverable transaction state. It argues that Saudi banks require controls that remain effective under partial failure, preserve deterministic evidence of what occurred, and support rapid reconciliation after service restoration. The review develops an integrated architecture in which API gateways, FIX sessions, feed handlers and workflow engines are protected by mutually reinforcing identity, cryptographic, observability, isolation and reconciliation controls. It further proposes lifecycle metrics that connect technical events with operational and financial consequences. The resulting framework contributes a bank-oriented model for securing electronic-trading integrations while preserving performance, auditability and continuity. Research gaps remain in empirical testing of FIX-specific attacks, cross-interface dependency modelling, market-data integrity benchmarks and Saudi-specific recovery exercises across banks, vendors and market infrastructures.