Jakub Klemsa

PhD student
Research Interests
Homomorphic Cryptography



Jakub Klemsa graduated in Mathematical Informatics programme at CTU in Prague with main interest in cryptography. In his diploma thesis, he proposed a novel extension to an attack against white-box implementations of ciphers. Thanks to these advances, he won an internship at Riscure, which is a world- class security lab. Currently, he is a third-year PhD student at CTU in Prague and his main focus is on theoretical guarantees as well as practical aspects of homomorphic cryptography.



  • Klemsa J. (2021, July). Fast and Error-Free Negacyclic Integer Convolution Using Extended Fourier Transform. In 2021 Cyber Security Cryptography and Machine Learning (CSCML). (pp. 282-300). Springer, Cham. [doi] [pdf]
  • Klemsa, J. (2021). TFHE Parameter Setup for Effective and Error-Free Neural Network Prediction on Encrypted Data. In Intelligent Computing (pp. 702-721). Springer, Cham. [doi] [pdf]


  • Klemsa, J., & Novotný, M. (2020, July). Exploiting Linearity in White-Box AES with Differential Computation Analysis. In Science and Information Conference (pp. 404-419). Springer, Cham. [doi] [pdf]
  • Klemsa, J., & Novotný, M. (2020, June). WTFHE: neural-netWork-ready Torus Fully Homomorphic Encryption. In 2020 9th Mediterranean Conference on Embedded Computing (MECO) (pp. 1-5). IEEE. [doi] [pdf]
  • Klemsa, J., & Trummová, I. (2020, February). Security Notions for the VeraGreg Framework and Their Reductions. In 2020 Third ISEA Conference on Security and Privacy (ISEA-ISAP) (pp. 8-20). IEEE. [doi] [pdf]


  • Říha, J., Klemsa, J., & Novotný, M. (2019, June). Multiprecision ANSI C Library for Implementation of Cryptographic Algorithms on Microcontrollers. In 2019 8th Mediterranean Conference on Embedded Computing (MECO) (pp. 1-4). IEEE. [doi] [pdf]


  • Klemsa, J., Kencl, L., & Vaněk, T. (2018, August). VeraGreg: A Framework for Verifiable Privacy-Preserving Data Aggregation. In 2018 17th IEEE International Conference On Trust, Security And Privacy In Computing And Communications/12th IEEE International Conference On Big Data Science And Engineering (TrustCom/BigDataSE) (pp. 1820-1825). IEEE. [doi] [pdf]