About Me

  • I’m a researcher at NTT Social Informatics Laboratories (formerly NTT Secure Platform Laboratories), NTT Corporation, Japan.
  • I joined NTT Corporation in 2012.
  • From 2019 to 2020, I was visiting researcher at Ruhr-university Bochum.
  • I received my Ph.D. from Kobe University in March 2017 (supervisor: Masakatu Morii).
  • The title of my Ph.D. thesis is “Integral Cryptanalysis against Symmetric-Key Cryptosystems.”
  • My research area is cryptography. Especially the design and analysis of symmetric-key cryptography.
  • Link : [dblp] [google scholar]
  • E-mail : todo[dot]yosuke[atmark]gmail[dot]com

Recent Major Activity

  • The paper “Improved Differential-Linear Attacks with Applications to ARX Ciphers” was accepted by the Journal of Cryptology. This paper is the extended version of our CRYPTO 2020 paper but contains significant technical improvements. 
  • The paper “A Modular Approach to the Incompressibility of Block-Cipher-Based AEADs” was accepted at Asiacrypt 2022.
  • The paper “Hybrid Code Lifting on Space-Hard Block Ciphers –Application to Yoroi and SPNbox” was accepted at IACR ToSC 2022, No. 3.
  • The paper “Cryptanalysis of Rocca and Feasibility of Its Security Claim” was accepted at IACR ToSC 2022, No. 3. 
  • The paper “New Attacks from Old Distinguishers, Improved Attacks on Serpent” was accepted at CT-RSA 2022. 
  • The paper “Perfect Trees: Designing Energy-Optimal Symmetric Encryption Primitives” was accepted at ToSC 2021, No. 4. 

Please check the page for publication list in detail.


  • Sep. 2020, IEICE Fundamentals Review Best Author Award, IEICE
  • Aug. 2020, CRYPTO 2020 Best Paper Award, IACR.
  • Jun. 2019, IEICE Best Papers Award, IEICE.
  • Jan. 2016, SCIS Best Papers Award, SCIS 2015, ISEC, IEICE.
  • Aug. 2015, CRYPTO 2015 Best Paper Award, IACR.
  • Aug. 2015, CRYPTO 2015 Best Young Researcher Award, IACR.

Program Committee

ASIACRYPT: 2016, 2018
CHES: 2021, 2022
Eurocrypt: 2016, 2020
FSE: 2018, 2019, 2020, (2021), 2022
Latincrypt: 2019
Selected Areas in Cryptography (SAC): 2019, 2020, 2021, 2022

Editorial Board

IACR Transactions on Symmetric Cryptology (ToSC) 2017–2022.
IACR Transactions on Cryptographic Hardware and Embedded Systems (TCHES) 2020–2022.


  • 2021 Trivium-LE and Triad-LE, Low-Energy Stream Ciphers
  • 2021 Sycon v2, Lightweight Cryptographic Permutation, and AEAD
  • 2020 Prince v2, Low-Latency Block Cipher
  • 2017 Gimli, Cross-Platform Cryptographic Permutation
  • 2017 GIFT, Lightweight Block Cipher
  • 2014 Minalpher, Authenticated Encryption with Associated Data