Since January 2023, I am a PhD candidate at Université Jean Monnet Saint-Etienne, in the SESAM team, under the supervison of Vincent Grosso and Pierre-Louis Cayrel. I work in embedded cryptography, with a focus on side-channnel and fault attacks and secure implementations.

From 2021 to 2022, I was a cryptography engineer at CryptoExperts where I mainly worked on White-Box Cryptography. From 2019 to 2021, I completed my Master in Cryptology and Information Security (Cryptis program) at Université de Limoges.

In my free time, I enjoy tackling crypto CTF challenges on some platforms such as CryptoHack and NSUCRYPTO.

Curriculum vitae: [pdf]

Publications

• SIFA on Nonce-based Authenticated Encryption: When Does It Fail? Application to Ascon
  Viet Sang Nguyen, Vincent Grosso, Pierre-Louis Cayrel
  Fault Diagnosis and Tolerance in Cryptography (FDTC) 2025
  [paper]
• Correlation Power Analysis on Ascon with Multi-bit Selection Function
  Viet Sang Nguyen, Vincent Grosso, Pierre-Louis Cayrel
  International Conference on Security and Cryptography (SECRYPT) 2025
  [paper] [code] (There are some flaws in this paper)
• Practical Persistent Fault Attacks on AES with Instruction Skip
  Viet Sang Nguyen, Vincent Grosso, Pierre-Louis Cayrel
  IACR Communications in Cryptography (CiC) 2025
  [paper] [code]
• Practical Second-Order CPA Attack on Ascon with Proper Selection Function
  Viet Sang Nguyen, Vincent Grosso, Pierre-Louis Cayrel
  CASCADE 2025
  [paper] [code]
• OBSCURE: Versalite Software Obfuscation from a Lightweight Secure Element
  Darius Mercadier, Viet Sang Nguyen, Matthieu Rivain, Aleksei Udovenko
  IACR Transactions of Cryptographic Hardware and Embedded Systems (CHES) 2024
  [paper] [code] [artifact]

Talks / Posters

• SIFA on Nonce-based Authenticated Encryption: When Does It Fail? Application to Ascon
  14/09/2025, at FDTC Kuala Lumpur, Malaysia
  [slides]
• SIFA on Nonce-based Authenticated Encryption: When Does It Fail? Application to Ascon
  03/07/2025, at SESAM seminar, in Laboratoire Hubert Curien, Saint-Étienne, France
  [slides]
• Correlation Power Analysis on Ascon with Multi-bit Selection Function
  11/06/2025, at SECRYPT, Bilbao, Spain
  [slides]
• Practical Second-Order CPA Attacks on Ascon with Proper Selection Function
  02/04/2025, at CASCADE, Saint-Etienne, France
  [slides]
• Attacks and Countermeasures in Persistent Fault Model
  01/10/2024, at JAIF, Rennes, France
  [slides][poster]
• Resistance of Threshold Implementations against Statistical (Ineffective) Fault Attacks
  18/06/2024, at Journée de la Recherche, Saint-Étienne, France
  Finalist in poster competition (top 11 among ~100), selected for presentation
  [slides][poster][video]
• Differential and Correlation Power Analysis on Ascon
  06/06/2024, at SESAM seminar, in Laboratoire Hubert Curien, Saint-Étienne, France
  [slides]
• Persistent Fault Model: Generalization, Cryptanalysis and Countermeasures
  16/10/2023, at Journées C2, in Najac, France
  [slides]
• Linear Cryptanalysis and Countermeasures in Persistent Fault Model
  22/06/2023, at SESAM seminar, in Laboratoire Hubert Curien, Saint-Étienne, France
  [slides]

Services

External Reviewer: EuroCrypt 2024, EuroCrypt 2025

Teaching

• Tutorials of C++ programming (33h),
  for first year bachelor students at IUT Saint-Étienne, 2023 - 2024
• Tutorials of embedded programming on CodeWarrior (27h x3)
  for second year bachelor students at IUT Saint-Étienne, 2023 - 2024

Master Thesis

Contact

Mail:
nvietsang [at] gmail.com
viet.sang.nguyen [at] univ-st-etienne.fr

Address:
Laboratoire Hubert Curien, Bâtiment F
18 rue du Professeur Benoît Lauras
42100, Saint-Étienne, France