I am a Principal Research Scientist and co-lead of the AI for Cyber Defence (AICD) Research Centre at the Alan Turing Institute. My work sits at the intersection of systems security and machine learning, with a focus on scalable methods for autonomous network defence and rigorous evaluation of AI cyber capabilities.
I lead national-scale efforts in modelling and mitigating AI-driven cyber threats, including the AI Cyber Risk Benchmark and the International AI Safety Report (2024–25), where I contributed the section on offensive capabilities. My research is embedded in both academic and policy spheres—shaping AI security standards at the EU AI Office, informing UK Parliament's resilience strategy for critical infrastructure, and steering the Turing's OpenAI early access safety testing.
My academic record spans top-tier venues. Some examples of my work include NeurIPS, ACM CCS, PETS and NDSS, while my applied work has been featured at Black Hat, Defcon, and CCC. I also serve as Area Editor (AI Security) for the Journal of Cybersecurity, and on the programme committees for several conference such as ICML, NeurIPS, KDD, RAID, AutoCyber etc.
Beyond core research, I have advanced the fields of hardware trojan detection, encrypted traffic analysis, and fair exchange protocols. My work on ultrasound tracking is now considered foundational, and tools I co-developed—such as the JCMathLib library that remains the only open-source cryptographic library for smartcards.
If you are a researcher or practitioner working on adversarial AI, critical infrastructure security, or scalable defences for emerging threats, feel free to reach out.
Encrypted Traffic Classification using High-dimensional Embeddings
This project studies the resilience of encrypted-communications schemes against adversaries that intent to breach the privacy of individual users. To evaluate widely-used schemes, we employ deep neural network models so as to map encrypted traffic traces into high-dimensional representations (see figure on the left). This enables us to generate a database of labeled traces that can then be used to classify unlabeled samples based on their proximity. Our results show that communication patterns suffice to reconstruct user activity with high accuracy and thus widely-deployed encrypted-communications systems offer weaker privacy guarantees than previously thought. This paper and the corresponding defence tools are currently under submission.[Paper]
Information Leakage Classification with Deep Neural Networks
Near-field microprobes have the capability to isolate small regions of a chip surface and enable precise measurements with high spatial resolution. Being able to distinguish the activity of small regions has given rise to attacks that exploit the spatial dependencies of cryptographic algorithms in order to recover the secret key. This project introduces a set of techniques that allow security researchers to evaluate the leakage properties of any chip. We show that deep neural network models outperform previously proposed methods (e.g., difference of means, multivariate templates), especially in the context of single-shot classification and small memory regions. We validate the practicality of our proposed models by classifying the leakages from the SRAM of a modern ARM Cortex-M4 chip. Our results show that we were able to always distinguish the activity between 2 SRAM regions of 128 bytes each, while for 256 SRAM single-byte regions we achieve 32% accuracy.[Paper]
MultiBallot: A Scheme for Privacy-preserving, Verifiable Statistics
Processing sensitive data for scientific purposes has the potential to bring substantial benefits both to individuals and society, however, it also requires strong guarantees that the data will not be used inappropriately. This project attempts to address some of the open challenges in the area: 1) effective ways to hold data processors accountable, 2) preserving the privacy of individuals and 3) protect the integrity of their data. For this purpose, we introduce MultiBallot, a privacy-preserving scheme that allows organizations to publish statistics derived from sensitive user data without breaching the privacy of the individual data subjects. Our scheme is based on ThreeBallot, a paper-voting design that allows voters to verify both the result of the elections (univariate operation) and that their individual vote was counted towards it. Our work extends this scheme and enables users to compute multivariate statistics on the published data. Moreover, MultiBallot can provide strong data integrity guarantees and public verifiability, when combined with a high-integrity data structure (e.g., a blockchain). These additional features make MultiBallot applicable in a wide range of data-processing scenarios such as healthcare statistics and communication records.[Paper]
Leakage-Resilient Protocols for Cryptographic Operations
Cryptographic devices used in critical applications operate under the assumption that hardware components remain always compliant with their specifications. Consequently, components that contain intentional or unintentional errors (e.g., bugs, hardware trojans, backdoors) cannot reliably maintain any of their security properties. In this work, we relax this strict correctness requirement and demonstrate how trusted, high-assurance hardware can be built from untrusted and potentially malicious components. We employ more than a hundred COTS secure cryptocoprocessors, verified to FIPS140-2 Level 4 tamper-resistance standards, and use them to realize high-confidentiality random number generation, key derivation, public key decryption and signing. Our experiments show a reasonable computational overhead (less than 1% for both Decryption and Signing) and an exponential increase in backdoor-tolerance as more ICs are added.Towards the Deployment of Realistic Autonomous Cyber Network Defence: A Systematic Review
Sanyam Vyas, Andrew Bolton, Vasilios Mavroudis, Peter Burnap, ACM Computing Surveys, 2025
International AI Safety Report
Yoshua Bengio et al., arXiv preprint arXiv:2501.17805, 2025
Humanity's Last Exam
Center for AI Safety, 2025
On Efficient Bayesian Exploration in Model-Based Reinforcement Learning
Alberto Caron, Vasilios Mavroudis, Chris Hicks, Transactions on Machine Learning Research, 2025
Deep Backdoors in Deep Reinforcement Learning Agents
Vasilios Mavroudis, Jamie Gawith, Sañyam Vyas, Chris Hicks, BlackHat US, 2024
SoK: Automated Vulnerability Detection
Shereen E., Dan Ristea, Sanyam Vyas, Sean McFadden, Martin Dwyer, Chris Hicks, Vasilios Mavroudis, 2024
AI Cyber Risk Benchmark: Automated Exploitation Capabilities
Dan Ristea, Vasilios Mavroudis, Chris Hicks, 2024
CybORG++: An Enhanced Gym for the Development of Autonomous Cyber Agents [Repository]
Harry Emerson, Lewis Bates, Chris Hicks, Vasilios Mavroudis, 2024
Online Convex Optimisation: The Optimal Switching Regret for all Segmentations Simultaneously [PDF]
Stephen Pasteris, Chris Hicks, Vasilios Mavroudis, Mark Herbster, NeurIPS, 2024 [Spotlight]
Entity-based Reinforcement Learning for Autonomous Cyber Defence
Isaac Thompson, Alberto Caron, Chris Hicks, Vasilios Mavroudis, Workshop on Autonomous Cybersecurity (AutonomousCyber), 2024
Environment Complexity and Nash Equilibria in a Sequential Social Dilemma
Mohammed Yasir, Andrew Howes, Vasilios Mavroudis, Chris Hicks, 17th European Workshop on Reinforcement Learning (EWRL), 2024
Autonomous Cyber Defence: Beyond Games?
Chris Hicks, Vasilios Mavroudis, Turing Report, 2024
International Scientific Report on the Safety of Advanced AI [PDF]
Yoshua Bengio, Davide Privitera, Tolga Besiroglu, Rishi Bommasani, Steven Casper, Yejin Choi, David Goldfarb, Homa Heidari, Laleh Khalatbari, Vasilios Mavroudis, Samuel Longpre, Interim Report, 2024
A View on Out-of-Distribution Identification from a Statistical Testing Theory Perspective
Alberto Caron, Chris Hicks, Vasilios Mavroudis, arXiv, 2024
Fusion Encoder Networks
Stephen Pasteris, Chris Hicks, Vasilios Mavroudis, arXiv, 2024
Mitigating Deep Reinforcement Learning Backdoors in the Neural Activation Space [PDF]
Sanyam Vyas, Chris Hicks, Vasilios Mavroudis, Deep Learning Security and Privacy Workshop (DLSP), 2024
Deep Reinforcement Learning for Denial-of-Query Discovery in GraphQL
Sean McFadden, Matteo Maugeri, Chris Hicks, Vasilios Mavroudis, Federico Pierazzi, Deep Learning Security and Privacy Workshop (DLSP), 2024
Nearest Neighbour with Bandit Feedback
Stephen Pasteris, Chris Hicks, Vasilios Mavroudis, NeurIPS, 2023
Adaptive Webpage Fingerprinting from TLS Traces
Vasilios Mavroudis, Jamie Hayes, IEEE/IFIP DSN, 2023
Reward Shaping for Happier Autonomous Cyber Security Agents
Ellie Bates, Vasilios Mavroudis, Chris Hicks, ACM AISec, 2023
Canaries and Whistles: Resilient Drone Communication Networks with (or without) Deep Reinforcement Learning
Chris Hicks, Vasilios Mavroudis, Myles Foley, Tom Davies, Karen Highnam, Thomas Watson, ACM AISec, 2023
Autonomous Network Defence Using Reinforcement Learning
Myles Foley, Chris Hicks, Karen Highnam, Vasilios Mavroudis, AsiaCCS, 2022
Inroads into Autonomous Network Defence using Explained Reinforcement Learning [PDF]
Myles Foley, Minyi Wang, Chris Hicks, Vasilios Mavroudis, CAMLIS, 2022
SIMple ID: QR Codes for Authentication Using Basic Mobile Phones in Developing Countries [PDF]
Chris Hicks, Vasilios Mavroudis, Jon Crowcroft, STM, 2022
An Interface Between Legacy and Modern Mobile Devices for Digital Identity [PDF]
Vasilios Mavroudis, Chris Hicks, Jon Crowcroft, ETAA, 2021
JCMathLib: Wrapper Cryptographic Library for Transparent and Certifiable JavaCard Applets [PDF]
Vasilios Mavroudis, Petr Svenda, IEEE EuroS&PW, 2020
Snappy: Fast Blockchain Payments [PDF]
Vasilios Mavroudis, Kevin Wuest, Aditi Dhar, Kari Kostiainen, Srdjan Capkun, NDSS, 2020
Location, Location, Location: Revisiting Modeling and Exploitation for Location-Based Side Channel Leakages [PDF]
Christoforos Andrikos, Lejla Batina, Lukasz Chmielewski, Lilian Lerman, Vasilios Mavroudis, Konstantinos Papagiannopoulos, Gilles Perin, George Rassias, Andrea Sonnino, AsiaCrypt, 2019
Libra: Fair Order-Matching for Electronic Financial Exchanges [PDF]
Vasilios Mavroudis, Henry Melton, AFT, 2019
Bounded Temporal Fairness for FIFO Financial Markets [PDF]
Vasilios Mavroudis, SPW, 2019
Market Manipulation as a Security Problem: Attacks and Defenses [PDF]
Vasilios Mavroudis, EuroSec, 2019
Towards Low-level Cryptographic Primitives for JavaCards
Vasilios Mavroudis, Petr Svenda, 2018
VAMS: Verifiable Auditing of Access to Confidential Data
Alex Hicks, Vasilios Mavroudis, Mustafa Al-Bassam, Sarah Meiklejohn, Steven Murdoch, 2018
Eavesdropping Whilst You’re Shopping: Balancing Personalisation and Privacy in Connected Retail Spaces [PDF]
Vasilios Mavroudis, Michael Veale (Equal Contribution), PETRAS/IoTUK/IET Living in the IoT Conference, 2018
A Touch of Evil: High-Assurance Cryptographic Hardware from Untrusted Components [PDF, ArXiv]
Vasilios Mavroudis, Andrea Cerulli, Petr Svenda, Daniel Cvrcek, Daniel Klinec, George Danezis, ACM CCS, 2017
CSAW 2018 Applied Research Competition Finalist
On the Privacy and Security of the Ultrasound Tracking Ecosystem [PDF]
Vasilios Mavroudis, Shuai Hao, Yanick Fratantonio, Fabio Maggi, Christopher Kruegel, Giovanni Vigna, PoPETs, 2017
Visual Analytics for Enhancing Supervised Attack Attribution in Mobile Networks [PDF]
Sotiris Papadopoulos, Vasilios Mavroudis, Alexandra Drosou, Dimitrios Tzovaras, ISCIS, 2014
LangChain v0.3
Vasilios Mavroudis, Preprints, https://doi.org/10.20944/preprints202411.0566.v1, November 2024
The Ultrasound Tracking Ecosystem.
Vasilios Mavroudis, Shuang Hao, Yanick Fratantonio, Federico Maggi, Giovanni Vigna, and Christopher Kruegel. November 2016
Correlation Analysis and Abnormal Event Detection Module.
EU FP7 Project: Enhanced Network Security for Seamless Provisioning in the Smart Mobile Ecosystem
Anomaly detection based on real-time exploitation of billing systems.
EU FP7 Project: Enhanced Network Security for Seamless Provisioning in the Smart Mobile Ecosystem
Anomaly detection within femtocell architectures.
EU FP7 Project: Enhanced Network Security for Seamless Provisioning in the Smart Mobile Ecosystem
Network information sources.
EU FP7 Project: Enhanced Network Security for Seamless Provisioning in the Smart Mobile Ecosystem
Crux: Privacy-preserving Statistics for Tor [PDF], Information Security Group, University College London, UK, 2015.
Supervisor: George Danezis
Cassiopeia: Real-time mobile security monitoring system, Dept. of Applied Informatics, University of Macedonia, Greece, 2012.
Supervisor: Ioannis Mavridis