A Hybrid Post-Quantum Cryptographic Framework for Secure Financial Infrastructures

Abstract

The advent of quantum computing introduces unprecedented threats to classical public-key cryptosystems underlying modern financial infrastructures. Current cryptographic primitives such as RSA and ECC are vulnerable to quantum algorithms like Shor’s, which can factor large integers and compute discrete logarithms efficiently on sufficiently powerful quantum hardware. As financial institutions protect decades of confidential transaction records and digital assets, transitioning to post-quantum security has become imperative. In this work, a hybrid cryptographic framework is developed that combines lattice-based key exchange with hash-based digital signatures to resist both classical and quantum attacks. The system was implemented within a simulated interbank settlement environment involving 12 participating nodes and evaluated under adversarial load. Key exchange times averaged 18.2 ms, while signature generation remained under 24.5 ms, suggesting feasibility for high-throughput financial messaging. The prototype also supports selective disclosure through zero-knowledge proofs to balance regulatory compliance and privacy. The results underscore the urgency of adopting quantum-safe cryptography across financial platforms, even as quantum hardware continues to mature. They also highlight trade-offs between performance, interoperability, and security in large-scale deployment.