I am a researcher in formal methods and secure systems. I develop mathematical models and automated tools, and apply them to analyse real-world systems, with a focus on privacy, security, knowledge, and coordination in complex systems. I am currently a Research Fellow in Secure Systems at the Surrey Centre for Cyber Security, University of Surrey, UK.
My research sits at the intersection of formal verification, applied cryptography, and multi-agent systems. I use logic, semantics, model checking, and automated reasoning to make security and privacy claims precise, rigorous, and verifiable.
Our current project explores the digitalisation of power-of-attorney schemes, focusing on the risks of fraud introduced by digitalisation, ways to mitigate existing fraud and abuse in traditional systems, and usability challenges for vulnerable individuals who may require third-party digital assistance. The project led to the ESORICS 2026 paper.
I investigated the security and privacy of the 3GPP AKMA protocol standard by formalising its security and privacy requirements, using tools such as Tamarin and Squirrel Prover to uncover privacy flaws, and proposing a privacy-enhanced version of AKMA.
This research resulted in two publications: EuroS&P 2025 and ASIACCS 2025.
I developed a framework for reasoning about and analysing privacy in cryptographic protocols. This involved designing a protocol model and a non-classical logic language for specifying privacy properties, building Phoebe as a model-checking tool for the framework, and analysing benchmark privacy-preserving protocols.
In 2024, the project received an Amazon Research Award to further enhance Phoebe. I co-authored several conference papers, including CSF 2024; our work on epistemic logic and AI reasoning received the Best Paper Award at FM 2023.
A complete list of my publications is available on DBLP.
Surrey Centre for Cyber Security · University of Surrey, UK
Surrey Centre for Cyber Security · University of Surrey, UK
RWTH Aachen University, MOVES group · Germany
Surrey Centre for Cyber Security, Department of Computer Science, University of Surrey · Guildford, Surrey, UK
Department of Mathematics, École Normale Supérieure, University of Antananarivo · Madagascar
Department of Mathematics and Applied Mathematics, University of Cape Town · South Africa
University of Stellenbosch · South Africa
University of Stellenbosch · South Africa
African Institute for Mathematical Sciences · South Africa
University of Antananarivo · Madagascar
Phoebe+: automated reasoning for provable privacy in cryptographic systems.
FM 2023 for work on semantics and verification of AI-centred programs.
I grew up in Madagascar, where Mathematics was always my favourite subject at school. I especially enjoyed geometry, probability, mechanics, maths puzzles and jokes. I began my undergraduate studies at the University of Antananarivo in 2006.
After obtaining two maîtrise degrees in 2009, in pure and applied mathematics, I was selected for the AIMS programme in South Africa. AIMS was a wonderful opportunity to study mathematics and computer science at an international level, with courses taught by renowned lecturers from across the world. It was also a great place to meet fellow African students and become part of a vibrant academic community. I stayed in South Africa for my MSc and PhD, working with Jeff Sanders on formal methods, knowledge, and privacy. I received a full DAAD scholarship for my PhD.
In 2016, I moved to Germany and joined the MOVES group at RWTH Aachen University as a visiting researcher. There, I worked on probabilistic programming and on reasoning about knowledge and information flow. After returning to Madagascar, I taught Mathematics and Programming at the École Normale Supérieure in Antananarivo from 2018 to 2019.
In 2020, I joined the University of Surrey, where I continue my academic adventure as a researcher in formal methods and secure systems.
Fortunat Rajaona, Ph.D. · Surrey Centre for Cyber Security · University of Surrey, Guildford, UK