Paper 2026/350

Hybridization of Cryptographic Primitives: A Generalized Framework for Adaptive Security

Abstract

Hybrid cryptographic schemes combine multiple primitives to provide resilience against diverse threats, particularly in the post-quantum era where classical algorithms face potential quantum attacks. However, existing hybrid approaches rely on predefined, fixed pairings of specific cryptographic algorithms, limiting their adaptability to evolving security requirements and heterogeneous deployment environments. This paper presents a generalized framework for the hybridization of cryptographic primitives that enables dynamic, user-driven composition of encryption schemes and digital signatures. Our approach leverages all-or-nothing transformations (AONTs) to construct hybrid schemes where an adversary must break all constituent primitives simultaneously to compromise the system. We formally prove that if at least one component scheme remains secure (IND-CPA for encryption, EUF-CMA for signatures), the entire hybrid construction achieves security equivalent to its strongest component. Unlike conventional approaches that prescribe specific algorithm combinations, our framework allows flexible selection and integration of classical, post-quantum, or mixed cryptographic primitives based on specific security requirements, computational constraints, and threat models. Our generalized hybridization methodology naturally extends to key encapsulation mechanisms and other cryptographic primitives, providing a foundation for building future adaptive cryptographic systems that remain secure even as individual components are compromised over time. This addresses a critical gap in current cryptographic practices and will provide users a methodology to construct flexible, robust security architectures for the post-quantum era.