Abstract
Abstract—The digital payment systems are quite popular these days. However, such payment systems are highly exposed to fraud, data breaches, and cyber attacks. The previous meth- ods which have used individual encryption algorithms cannot be trusted when encrypting financial transactions these days. In order to solve this problem, this paper presents a new hybrid cryptographic payment system called SecurePay, which will use the following elements: AES-256 encryption algorithm, RSA-2048 digital signature algorithm, ECC-P256 key exchange method, SHA-256 hash function, blockchain technology, and fraud detector. The first algorithm will be used for encrypting transactions because it provides a fast encryption process, RSA- 2048 is an authentication and digital signature-based encryption algorithm, and ECC-P256 will be used for the secure exchange of keys. The transaction details will be stored securely thanks to the blockchain module. The fraud detector module will allow the detection of fraudulent transactions based on patterns of transactions. It is clear from the experiment results that the average encryption times were 0.0773 ms for AES-256, 0.1893 ms for ECC-P256, and 0.5455 ms for RSA-2048. It can be seen that the proposed hybrid cryptosystem has a high level of security and low latency. All in all, the SecurePay system is a versatile, secure, and efficient solution to the contemporary online payment system. Index Terms—Hybrid cryptography, AES-256, RSA-2048, ECC-P256, blockchain security, digital payments, fraud detec- tion, secure transactions, fintech security, SHA-256