CVE-2026-33583

Exposure of the QKEY used as input into the ‘OTA-Quantum’ device registration process and internal system keys via an unauthenticated and unencrypted HTTP GET method in the Arqit Symmetric Key Agreement Platform. This issue affects Symmetric Key Agreement Platform: before 26.03...

Quantum Resonance Encryption for Secure Data Storage and Communication with Quantum Kicked Top

In a shared quantum computer, how to ensure data privacy and protection from access by unauthorized parties? We propose a genuine quantum protocol for protecting user's data which is not accessible even to the service provider. The protocol is based on quantum kicked top -- the dynamics of a spin...

Practical Countermeasure against Attacks Exploiting Detection Efficiency Mismatch in Quantum Key Distribution

We demonstrate a practical countermeasure against a well-known class of attacks on quantum key distribution QKD systems that exploit detection efficiency mismatch, where the receiver's detectors do not exhibit identical responses to incoming photons across all degrees of freedom. This class of...

CVE-2026-33583

Exposure of the QKEY used as input into the ‘OTA-Quantum’ device registration process and internal system keys via an unauthenticated and unencrypted HTTP GET method in the Arqit Symmetric Key Agreement Platform. This issue affects Symmetric Key Agreement Platform: before 26.03...

Numerical Security Analysis for Practical Quantum Key Distribution

Quantum key distribution QKD promises information-theoretic security based on quantum mechanics and idealized device models. Practical implementations, however, deviate from these models due to unavoidable device imperfections, and existing security proofs fall short of capturing the complexity o...

Security of Decoy-State Quantum Key Distribution with Correlated Bit-And-Basis Encoders

Practical quantum key distribution QKD modulators inevitably introduce correlations, causing the state emitted in a given round to depend on the setting choices made in previous rounds. These correlations break the round-by-round independence structure on which many widely used security proof...

Rigorous Security Proofs for Practical Quantum Key Distribution

This thesis is concerned with rigorous security analyses of practical Quantum Key Distribution QKD protocols, using a variety of modern proof techniques. The main results are as follows. First, we establish a security proof for variable-length QKD protocols against IID collective attacks, and...

Quantum-Safe IPsec in the Banking Industry

The emergence of Cryptographically Relevant Quantum Computers CRQCs presents a critical threat to classical cryptographic systems, particularly widely adopted protocols such as RSA, Diffie-Hellman DH, and Elliptic Curve Cryptography ECC. Given their extensive use in the financial sector, the adve...

PQC-Enhanced QKD Networks: A Layered Approach

We present a layered and modular network architecture that combines Quantum Key Distribution QKD and Post-Quantum Cryptography PQC to provide scalable end-to-end security across long distance multi-hop, trusted-node quantum networks. To ensure interoperability and efficient practical deployment,...

The Manipulate-And-Observe Attack on Quantum Key Distribution

Quantum key distribution is often regarded as an unconditionally secure method to exchange a secret key by harnessing fundamental aspects of quantum mechanics. Despite the robustness of key exchange, classical post-processing reveals vulnerabilities that an eavesdropper could target. In particula...

Quantum Bit Error Rate Analysis in BB84 Quantum Key Distribution: Measurement, Statistical Estimation, and Eavesdropping Detection

Quantum Key Distribution QKD provides information-theoretic security by exploiting the principles of quantum mechanics. Among QKD protocols, the BB84 scheme remains the most widely adopted for both theoretical research and practical implementation. A critical parameter determining the reliability...

Full Network Nonlocality Based Security in Quantum Key Distribution

In the last decade research of quantum nonlocality has moved beyond the regime of standard Bell nonlocality to consider network-based experimental set-ups involving multiple independent sources. Notion of full network nonlocality has emerged as some truly network phenomena that cannot be realized...

Secure Quantum Communication: Simulation and Analysis of Quantum Key Distribution Protocols

Quantum computing poses significant threats to conventional cryptographic techniques such as RSA and AES, motivating the need for quantum secure communication methods. Quantum Key Distribution QKD offers information theoretic security based on fundamental quantum principles. This paper presents a...

Quantum CDMA-Based Continuous Variable Quantum Key Distribution Using Chaotic Phase Shifters

We present a quantum code-division multiple-access q-CDMA framework for multiuser continuous-variable quantum key distribution CV-QKD over a shared quantum channel. The proposed architecture employs chaotic phase shifters to encode and decode quantum states, enabling efficient multiplexing and...

Energy-Time Attack on Detectors in Quantum Key Distribution

Quantum key distribution is unbreakable in theory but may be hacked via imperfections in its hardware implementations. While many imperfections have been mitigated by countermeasures and advanced security proofs, several remain unsolved. One of these is a superlinear behaviour in single-photon...

Machine Learning Techniques for Enhancing Quantum Key Distribution

Quantum Key Distribution QKD offers theoretically unbreakable security by leveraging quantum mechanics. However, practical implementation is challenged by environmental vulnerabilities, noise, and hardware imperfections. Recently, Machine Learning ML has emerged as a powerful tool to address thes...

Recovery-Induced Erasure Attack on QKD Systems

Detector dead time is typically treated as a fixed parameter in quantum key distribution QKD security analyses. In practice, however, the effective recovery time of single-photon avalanche photodiodes SPADs depends on the incident count rate. In this work, we demonstrate that this...

Power Network SCADA Quantum Communications: A Comparison of BB84, B92, E91, and SGS04 Quantum Key Distribution Protocols

The current state, emerging trends, and practical challenges of optical fiber-based power network SCADA quantum communication must be addressed to fully utilise the technological platform's potential in real-world power system SCADA communications involving massive volumes of real-time data, as...

Strengthening Security and Noise Resistance in One-Way Quantum Key Distribution Protocols through Hypercube-Based Quantum Walks

Quantum Key Distribution QKD is a foundational cryptographic protocol that ensures information-theoretic security. However, classical protocols such as BB84, though favored for their simplicity, offer limited resistance to eavesdropping, and perform poorly under realistic noise conditions. Recent...

Eve'S Forgery Probability from Her False Acceptance Probability: Interactive Authentication, Holevo Information and the Min-Entropy

We obtain estimates for Eve's forgery probability, namely the probability that she is able to forge a message which Alice or Bob mistakenly accept over a noisy Quantum channel for generating a shared Quantum secret key. This probability is related to Eve's success probability obtained in a previo...