Takanori Isobe

I am an Associate Professor at University of Hyogo since April 2017. Previously I worked at Sony Corporation from 2008 to 2017 (nine years) as a researcher of information security and cryptography. I was a Visiting Researcher of Technical University of Denmark from 2014 to 2015. I received PhD degree from Kobe University in 2013.

News

  • August 2019, I will organize ASK 2019 as general and program co-chair.
  • August 2019, Two papers are accepted to FSE 2020/ToSC2019
  • June 2019, Two papers are accepted to SAC 2019
  • May 2019, I am invited to program committee of ASIACRYPT 2019
  • April 2019, A paper is accepted to CRYPTO 2019.
  • Jan. 2019, I (will) serve on program committee of FSE 2020/ToSC2019
  • Oct. 2018, I (will) serve on program committee of SAC 2019
  • Jun. 2018, A paper of security analysis of E2EE of LINE (Letter sealing) is accepted to ESORICS 2018
    • Takanori Isobe and Kazuhiko Minematsu, "Breaking the Message Integrity of End-to-End Encryption Schemes of LINE"
      • Full version is available at eprint
  • May. 2018, Two papers are accepted to FSE 2019/ToSC2018
  • May. 2018, Two papers are accepted to CRYPTO 2018.
  • I (will) serve on program committee of ASIACRYPT 2018 and FSE2019/ToSC2018
  • Dec. 2017. I found several vulnerabilities of E2EE of LINE (Letter sealing) with Kazuhiko Minematsu
    • These are officially recognized as a vulnerability of "Encryption Break" by LINE corporation via BUG bounty program.
    • I will present it at SCIS 2018
      • Impersonation and Forgery Attacks on End-to-End encryption of LINE (in Japanese)

My research interest is

  • Whitebox Cryptography
  • Design of Lightweight/Low Energy Ciphers
  • Cryptanalysis of Symmetric Key Cryptography
  • Security Analysis of Real-world Products and System
  • End-to-End Encryption

I am a designer of

  • Lightweight block cipher: Piccolo
  • Lightweight stream cipher: LILLE
  • Low energy block cipher: Midori
  • Whitebox-secure block ciphers: SPACE and SPNbox

Program Committee : ASIACRYPT 2019, INDOCRYPT 2019, FSE2020/ToSC2019, SAC2019, INDOCRYPTO2018, ASIACRYPT 2018, FSE2019/ToSC2018, FSE 2016, INDOCRYPT 2016

Reviewer: CRYPTO, EUROCRYPT, ASIACRYPT, FSE, CHES, SAC, CT-RSA, ACISP, INDOCRYPT , etc.

DBLP, Google Scholar


[Selected Publication (IACR Publication and CCS )]

  1. Subhadeep Banik, Khashayar Barooti and Takanori Isobe, "Cryptanalysis of Plantlet ", IACR Trans. Symmetric Cryptol (ToSC/FSE), 2019. (to appear).
  2. Fukang Liu, Christoph Dobraunig, Florian Mendel, Takanori Isobe , Gaoli Wang and Zhenfu Cao, "New Semi-Free-Start Collision Attack Framework for Reduced RIPEMD-160 ", IACR Trans. Symmetric Cryptol (ToSC/FSE),2020. (to appear).
  3. Fukang Liu, Christoph Dobraunig, Florian Mendel, Takanori Isobe, Gaoli Wang and Zhenfu Cao, "Efficient Collision Attack Frameworks for RIPEMD-160", CRYPTO 2019.
  4. Takanori Isobe and Kazuhiko Minematsu, "Breaking the Message Integrity of End-to-End Encryption Schemes of LINE", ESORICS 2018.
  5. Yosuke Todo, Takanori Isobe, Willi Meier, Kazumaro Aoki, and Bin Zhang, "Fast Correlation Attack Revisited --Cryptanalysis on Full Grain-128a, Grain-128, and Grain-v1", CRYPTO 2018
  6. Qingju Wang, Yonglin Hao, Yosuke Todo, Chaoyun Li, Takanori Isobe, Willi Meier, "Improved Division Property Based Cube Attacks Exploiting Algebraic Properties of Superpoly", CRYPTO 2018
  7. Gianira N. Alfarano,Christof Beierle, Takanori Isobe, Stefan Kölbl, Gregor Leander, "ShiftRows Alternatives for AES-like Ciphers and Optimal Cell Permutations for Midori and Skinny", ToSC/FSE 2018
  8. Subhapeep, Banik, Vasily Mikhalev, Frederik Armknecht, Takanori Isobe, Willi Meier, Andrey Bogdanov, Yuhei Watanabe, Francesco Regazzoni, "Toward Low Energy Stream Ciphers", ToSC/FSE 2018
  9. Subhadeep Banik, Takanori Isobe, Tingting Cui and Jian Guo , “Some cryptanalytic results on Lizard ”, ToSC/FSE 2017.
  10. Takanori Isobe and Kyoji Shibutani, "New Key Recovery Attacks on Minimal Two-Round Even-Mansour Ciphers", ASIACRYPT 2017.
  11. Yosuke Todo, Takanori Isobe, Yonglin Hao, and Willi Meier, "Cube Attacks on Non-Blackbox Polynomials Based on Division Property", CRYPTO 2017.
  12. Subhadeep Banik, Andrey Bogdanov, Takanori Isobe and Martin Bjerregard jepsen. “Analysis of Software Countermeasures for Whitebox Encryption.” ToSC/FSE 2017
  13. Andrey Bogdanov , Takanori Isobe and Elmar Tischhauser, “Towards Practical Whitebox Cryptography: Optimizing Efficiency and Space Hardness”, ASIACRYPT 2016.
  14. Subhadeep Banik and Takanori Isobe, " Cryptanalysis of the Full Spritz Stream Cipher”, FSE 2016.
  15. Andrey Bogdanov and Takanori Isobe, “White-Box Cryptography Revisited: Space-Hard Ciphers”, ACM Conference on Computer and Communications Security (CCS) 2015.
  16. Subhadeep Banik, Andrey Bogdanov, Takanori Isobe, Kyoji Shibutani, Harunaga Hiwatari, Toru Akishita, Francesco Regazzoni, “Midori: A Block Cipher for Low Energy”, ASIACRYPT 2015.
  17. Andrey Bogdanov and Takanori Isobe, “How Secure is AES Under Leakage”, ASIACRYPT 2015..
  18. Takanori Isobe and Kyoji Shibutani, " Improved All-Subkeys Recovery Attacks on FOX, KATAN and SHACAL-2 Block cipher”, FSE 2014.
  19. Takanori Isobe, "A Single Key Attack on the Full GOST Block Cipher", Journal of Cryptology, 2013.
  20. Takanori Isobe and Kyoji Shibutani, "Generic Key Recovery Attack on Feistel Scheme”, ASIACRYPT 2013.
  21. Takanori Isobe, Toshihiro Ohigashi, Yuhei, Watanabe and Masakatu Morii, "Full Plaintext Recovery Attack on Broadcast RC4”, FSE 2013.
  22. Li Ji, Takanori Isobe and Kyoji Shibutani, "Converting Meet-in-the-Middle Preimage Attack into Pseudo Collision Attack: Application to SHA-2”, FSE 2012.
  23. Kyoji Shibutani, Takanori Isobe, Harunaga Hiwatari, Atsushi Mitsuda, Toru Akishita and Taizo Shirai, "Piccolo : A Ultra-Lightweight Blockcipher" CHES 2011.
  24. Takanori Isobe, "A Single Key Attack on the Full GOST Block Cipher", FSE 2011 (Best Paper Award)
  25. Takanori Isobe and Kyoji Shibutani, "Preimage Attack on Reduced Tiger and SHA-2”, FSE 2009 .


Contact: takanori.isobe(at)ai(dot)u-hyogo(dot)ac(dot)jp