Prevention of Secured websites from Downgrade and MITM attacks through Blocash Technology

Online transaction websites face persistent threats from SSL strip, downgrade, and man-in-the-middle attacks, which exploit vulnerabilities in SSL/TLS protocols to intercept sensitive user data. Traditional reliance on transport-layer security leaves gaps when connections are compromised, exposing plaintext data during transmission. This paper proposes a multi-layered security framework that shifts encryption to the client side, combining AES-GCM 256 encryption on the frontend with a secure RSA- based key exchange and dual-hash authentication on the backend. By encrypting transaction data in real-time before transmission and verifying its integrity with a dual-hash mechanism, the solution ensures confidentiality and authenticity, even over downgraded or intercepted channels. Optimized for performance using WebAssembly, this approach reduces the attack surface and outperforms conventional methods in resilience against targeted cyber threats. We demonstrate its efficacy through a practical implementation tailored for fintech applications, offering a scalable, trust-enhancing defense for modern web-based transactions.