Joint PhD Research – Andreas Bernhard & Mathias Pfister
Research Context
Applied Cryptography · Systems Security · AI Safety · Information Theory · Critical Infrastructure Protection · Decision Science
Critical infrastructure organisations face a fundamental dilemma: they must analyse and share information about their vulnerabilities and risks to improve collective security, yet this very information becomes a high-value target for adversaries. Current approaches rely on trusted central authorities (government agencies, sector ISACs) to aggregate and analyse risk data, creating single points of failure.
Simultaneously, AI-based tools are increasingly proposed for security risk assessment, but their reliability, consistency, and potential biases in safety-critical contexts remain poorly understood. There is no systematic empirical foundation comparing human expert judgment with AI capabilities, nor comprehensive benchmarking across different AI models for critical infrastructure scenarios.
"How can a society analyse its greatest risks — without those risks becoming its greatest vulnerability?"
While prior work has addressed secure multi-party computation and privacy-preserving protocols, and separate research streams have evaluated AI capabilities in various domains, no work to date has formally integrated cryptographic confidentiality guarantees with empirical AI evaluation in the context of adversarially sensitive risk information.
Existing zero-knowledge architectures focus on financial transactions or identity verification, not on collaborative threat intelligence. Similarly, AI benchmarking in security contexts lacks formal analysis of what happens when the assessment process itself becomes an attack vector. This research addresses both gaps simultaneously and explores their intersection.
To the best of our knowledge, no existing work formally combines cryptographically enforced confidentiality architectures with systematic, cross-model AI evaluation for adversarially sensitive risk information in critical infrastructure contexts.
Core Novelty
This work is the first to formally combine zero-knowledge risk architectures with empirical, cross-model AI evaluation for adversarially sensitive critical-infrastructure data.
This work investigates formal cryptographic models for handling adversarially sensitive risk information without requiring trust in a central authority. The term "zero-knowledge" is used here in the architectural and information-theoretic sense (not limited to formal ZKP constructions): minimizing information disclosure about individual vulnerabilities while enabling aggregate risk assessment. The research employs secure multi-party computation (MPC), functional encryption, and information-theoretic analysis to establish provable security guarantees.
Research Hypotheses:
Cryptographic Primitives & Techniques:
Homomorphic encryption · Attribute-based encryption · Zero-knowledge proofs (zk-SNARKs) · Secure multi-party computation · Differential privacy · Information-theoretic security bounds · STRIDE threat modeling · Dolev-Yao adversary model
The research aims to establish formal security proofs, develop architectural designs with provable confidentiality guarantees, and evaluate breach scenarios through simulation-based analysis comparing centralized versus decentralized information leakage.
This work evaluates whether large language models can provide reliable risk assessment in critical infrastructure contexts through systematic empirical analysis, using controlled experimental designs and statistical hypothesis testing.
Research Hypotheses:
Evaluation Framework:
Controlled experimental design · Statistical hypothesis testing · Inter-rater reliability (Fleiss' kappa, Krippendorff's alpha) · Calibration analysis · Adversarial robustness testing · Bias detection (demographic, temporal, domain-specific) · Explainability metrics (SHAP, attention analysis)
The research aims to develop a standardized benchmark dataset of critical infrastructure risk scenarios (n > 100), conduct controlled experiments with human security experts (n > 30) and multiple large language models (ChatGPT, Claude, LLaMA, Gemini, Mistral), and perform statistical analysis to evaluate the stated hypotheses.
The two research tracks converge in investigating an integrated evaluation framework for secure, AI-assisted risk assessment systems. Track A establishes the cryptographic foundation ensuring that sensitive risk data can be processed collaboratively without centralized trust assumptions. Track B provides empirical evidence determining which AI capabilities can be reliably integrated and where human oversight remains necessary.
Joint research activities include: (1) development of shared evaluation scenarios with controlled information disclosure levels, (2) formal analysis of security-usability trade-offs in human-AI-crypto systems, (3) architectural framework design demonstrating provable security properties while incorporating empirically validated AI assessment capabilities, and (4) evaluation of the combined system under realistic threat scenarios.
Security Architect, Swiss Armed Forces (Cyber Command)
Deputy Information Security Officer, SBB Infrastructure Division
Both researchers focus on the intersection of cryptography, critical infrastructure protection, and AI-assisted risk analysis.
Both researchers will collaborate on:
48 Months · Two parallel dissertations · Joint publications
Problem Formalization & Foundations
Literature review · Coursework · Formal model development · Pilot studies · Initial framework design · Hypothesis formulation
Prototyping & Data Collection
Cryptographic architecture design · Security proofs · Controlled experiments · Dataset development · First publications (conferences)
Formal Verification & Model Comparison
Correctness proofs · AI model benchmarking · Statistical hypothesis testing · Integration of both tracks · Additional publications (journals)
Consolidation, Publications & Thesis
Comprehensive system evaluation · Final statistical analysis · Dissertation writing · Final publications · Defense preparation
Expected Research Output
The combined results aim to inform:
"How can a society analyse its greatest risks — without those risks becoming its greatest vulnerability?"