Quantum computers that can run Shor's algorithm are expected to become available in the next decade. These algorithms can be used to break conventional digital signature schemes (e.g. RSA or ECDSA), which are widely used in embedded systems today. This puts these systems at risk when they are used in safety-relevant long-term applications such as automotive systems or critical infrastructures. To mitigate this risk, classical digital signature schemes used must be replaced by schemes secure against quantum computer based attacks.
Quantum computers that can run Shor's algorithm are expected to become available in the next decade. These algorithms can be used to break conventional digital signature schemes (e.g. RSA or ECDSA), which are widely used in embedded systems today. This puts these systems at risk when they are used in safety-relevant long-term applications such as automotive systems or critical infrastructures. To mitigate this risk, classical digital signature schemes used must be replaced by schemes secure against quantum computer based attacks.
The rapid advancement of quantum computing presents a significant challenge to classical cryptographic systems that underpin modern digital security infrastructures. In particular, RSA-2048 encryption, widely deployed in banking and financial institutions for secure transactions, relies on the computational hardness of integer factorization. However, the emergence of quantum algorithms—especially Shor’s algorithm—poses a fundamental threat to RSA security by enabling polynomial-time factorization of large integers on sufficiently powerful quantum computers. This case study investigates the vulnerability of RSA-2048 within a banking environment, analyzing the mathematical foundations of the threat, potential timelines for quantum feasibility, and associated cybersecurity risks. The study further examines the implications for financial data protection, digital signatures, and secure communication channels. In response to these emerging risks, the paper explores post-quantum cryptographic alternatives, including lattice-based, hash-based, and code-based schemes, and evaluates their suitability for banking applications. The findings emphasize the urgency of transitioning toward quantum-resistant cryptographic frameworks and propose strategic recommendations for proactive cryptographic migration to ensure long-term data confidentiality and system resilience.
Traditional cryptographic systems that are based on algorithms such as RSA, ECC, and DH are becoming increasingly vulnerable to quantum-based attacks. This is especially the case attributable to algorithms such as Shor’s, which are able to factor large integers and solve discrete logarithms in an efficient manner. There has been a rapid advancement in quantum computing. There is a significant risk to the integrity, confidentiality, and security of the data that a result of this. Cryptographic algorithms that are immune to both classical and quantum attacks are the goal of post-quantum cryptography, often known as PQC. The purpose of this study is to investigate a variety of post-quantum algorithms, including lattice-based, hash-based, code-based, multivariate, and isogeny-based cryptography, and to evaluate the possibility of these algorithms to successfully defend against future quantum attacks. Within the context of real-world applications, we dissect the security assumptions, performance indicators, and issues that these algorithms present. In addition to this, we investigate the current efforts that are being made to standardize PQC through projects such as the NIST post-quantum cryptography work. In order to ensure the safety of data over the long term, this study offers some insights into the process of developing cryptographic methods that are durable in preparation for the era of quantum computing.
The emergence of large-scale quantum computing presents a fundamental challenge to widely deployed classical cryptographic systems.Public-key algorithms such as RSA and Elliptic Curve Cryptography (ECC) rely on mathematical problems that are considered computationally infeasible for classical computers but can potentially be solved efficiently by sufficiently capable quantum computers using Shor's algorithm.Symmetric cryptography is less severely affected, although Grover's algorithm reduces the effective security provided by a fixed key length.Replacing every existing cryptographic system immediately with post-quantum cryptography is neither technically nor operationally straightforward.Financial institutions, government organisations and large enterprises operate extensive cryptographic infrastructures involving legacy applications, APIs, certificates, hardware security modules, databases, digital signatures, mobile applications and third-party systems.This paper proposes a Classical Cryptography Quantum Hardening Framework (CCQHF) that combines cryptographic inventory, risk classification, hybrid cryptographic mechanisms, increased symmetric-key strength, cryptographic agility, key-management improvements and staged adoption of post-quantum cryptography.The framework does not claim to make RSA or ECC resistant to Shor's algorithm.Instead, it proposes a controlled architecture in which classical cryptography is retained where appropriate while quantum-vulnerable components are protected through hybrid mechanisms and ultimately replaced by standardised post-quantum algorithms.
Abstract It is viewed as revolutionary technology, offering incredible potential in terms of computing power within different scientific and industrial sectors. Quantum computers provide remarkable computing power; however, they also present significant security risks to existing public-key cryptography systems used to secure digital communication, online banking systems, government, medical applications, cloud computing systems, and IoT systems. Security of commonly used encryption schemes like RSA, DH, and ECC depends on mathematical problems that are impossible for classical computers to solve but can be easily resolved with the help of powerful enough quantum computers by using Shor’s algorithm. Furthermore, Grover’s algorithm makes exhaustive search attacks much faster, thus effectively lowering the security level of symmetric encryption schemes since it provides the speed-up for brute-force attacks. Post-Quantum Cryptography (PQC) turned out to be an effective and scalable method to protect digital data from attacks using quantum computing. In contrast to quantum cryptography, which requires a special quantum communication channel, PQC uses classical cryptographic algorithms that cannot be broken down by either classical or quantum computer due to certain mathematical problems. This research paper offers an extensive exploration of post-quantum cryptography through the analysis of the development of quantum computing, weaknesses of current cryptographic techniques, and mathematics behind quantum-resistant algorithms. Moreover, this paper explores the major classes of PQC techniques such as lattice-based, code-based, hash-based, multivariate, and isogeny-based cryptography and provides details about their security and application. Moreover, the report gives an overview of the NIST Post-Quantum Cryptography Standardization Project and analyzes recent standardizations of quantum-proof algorithms to be utilized in future digital infrastructures. Keywords: Post-Quantum Encryption, Quantum Security, Quantum-Proof Public-Key Cryptography, Lattice-Based Security Protocols, ML-KEM Key Encapsulation Mechanism, ML-DSA Digital Signature Algorithm, NIST Post-Quantum Cryptography, Contemporary Cybersecurity, Secure Communications, Cryptographic Algorithms.
Quantum computing represents one of the most disruptive technological advancements of the 21st century, with profound implications for modern cryptographic systems. Traditional digital signature algorithms—such as RSA, DSA, and Elliptic Curve Cryptography (ECC)—derive their security from mathematical problems like integer factorization and discrete logarithms, which are computationally infeasible for classical computers. However, the advent of quantum algorithms, particularly Shor’s and Grover’s algorithms, poses a direct threat to these cryptographic assumptions by drastically reducing the time required to solve such problems. This development renders existing Digital Signature infrastructures potentially obsolete once large-scale quantum computers become operational. To counter this threat, researchers have proposed a range of post-quantum cryptographic (PQC) algorithms, including lattice-based, hash-based, and multivariate polynomial-based signature schemes, which are designed to resist quantum attacks. This paper critically examines the extent of quantum vulnerability in current Digital Signature systems and evaluates the comparative performance, efficiency, and security trade-offs of post-quantum alternatives. The study aims to provide a structured understanding of the ongoing transition toward quantum-resistant digital authentication and to propose a roadmap for secure implementation in future cryptographic environments.