Selected Publications:

• IACR Conference
  1. New Key Recovery Attack on HMAC/NMAC-MD4 and NMAC-MD5, by Lei Wang and Kazuo Ohta and Noboru Kunihiro
     in Proc. of Eurocrypt2008, LNCS4965, pp. 237-253, 2008.
  2. Improved Collision Search for SHA-0, by Yusuke Naito, Yu Sasaki, Takeshi Shimoyama, Jun Yajima, Noboru Kunihiro and Kazuo Ohta,
     in Proc. of Asiacrypt2006, LNCS 4284, pp. 21-36, December 3-7, 2006, Shanghai, China.
  3. Modulus Search for Elliptic Curve Cryptosystems, by Koyama K., Tsuruoka Y. and Kunihiro, N.
     In Advances in Cryptology -- Asiacrypt'99, LNCS 1716, pp. 1-7 (1999).
  4. Equivalence of Counting the Number of Points on Elliptic Curve over the ring $Z_n$ and Factoring $n$, by Noboru Kunihiro and Kenji Koyama
     In Proceeding of Advances in Cryptology -- EUROCRYPT'98, LNCS 1403, pp. 47-58 (1998).
• IACR Workshop
  1. Deterministic Polynomial Time Equivalence between Factoring and Key-Recovery Attack on Takagi's RSA, by Noboru Kunihiro and Kaoru Kurosawa
     in Proc. of PKC2007, LNCS4450, pp. 412-425, April 16-20, Beijing, China.
  2. New Message Difference for MD4, by Y. Sasaki, L. Wang, K. Ohta and N. Kunihiro
     in Proc. of FSE 2007, LNCS4593, pp. 329-348, March 26-28, 2007, Luxembourg.
• Other Crypto Conference (Refereed)
  • 2008
    • Sanitizable and Deletable Signature, by Tetsuya Izu, Noboru Kunihiro, Kazuo Ohta, Makoto Sano and Masahiko Takenaka,
      in Proc. WISA2008, LNCS5379, pp. 130-144, 2008.
    • Extension of Secret Handshake Protocols with Multiple Groups in Monotone Condition, by Yutaka Kawai, Shotaro Tanno, Takahiro Kondo, Kazuki Yoneyama, Noboru Kunihiro and Kazuo Ohta,
      in Proc. WISA2008, LNCS5379, pp. 160-173, 2008.
    • New Definition of Density on Knapsack Cryptosystems, by Noboru Kunihiro
      in Proc. of AfricaCrypt2008, LNCS5023, pp. 156-173, 2008.
    • Password Recovery on Challenge and Response: Impossible Differential Attack on Hash Function, by Yu Sasaki, Lei Wang, Kazuo Ohta, Noboru Kunihiro
      in Proc. of AfricaCrypt2008, LNCS5023, pp. 290-307, 2008.
    • Security of MD5 Challenge and Response: Extension of APOP Password Recovery Attack, by Yu Sasaki, Lei Wang, Kazuo Ohta and Noboru Kunihiro
      in Proc. of CT-RSA2008, LNCS4964, pp. 1-18, 2008.
    • Small Secret Key Attack on a variant of RSA (due to Takagi), by Kouichi Itoh and Noboru Kunihiro and Kaoru Kurosawa
      in Proc. of CT-RSA2008, LNCS4964, pp. 387-406, 2008.
    • Password Recovery Attack on Authentication Protocol MD4(Password||Challenge), by Lei Wang and Kazuo Ohta and Noboru Kunihiro
      in Proc. of ASIACCS2008, pp. 3-9, 2008.
    • A Strict Evaluation Method on the Number of Conditions for the SHA-1 Collision Search, by Jun Yajima, Terutoshi Iwasaki, Yusuke Naito, Yu Sasaki, Takeshi Shimoyama, Noboru Kunihiro, Kazuo Ohta
      in Proc. of ASIACCS2008, pp. 10-20, 2008.
  • 2007
    • A New Strategy for Finding a Differential Path, by Jun Yajima, Yu Sasaki, Yusuke Naito, Terutoshi Iwasaki, Takeshi Shimoyama, Noboru Kunihiro, Kazuo Ohta
      in Proc. of ACISP 2007, LNCS4586, pp. 45-58, July, 2007.
    • Sanitizable Signature with Aggregation, by Tetsuya Izu, Noboru Kunihiro, Kazuo Ohta, Masahiko Takenaka and Takashi Yoshioka
      in Proc. of ISPEC 2007, LNCS4464, pp.51-64, May 7-9, 2007, Hong Kong, China.
  • 2006
    • Factoring Square-free Composite Integer by solving Multivariate Integer Polynomial Equations, by Bagus Santoso, Noboru Kunihiro, Naoki Kanayama and Kazuo Ohta,
      in Proc. of Vietcrypt2006, LNCS4341, pp. 243-259,September 25-28, 2006, Hanoi, Vietnam.
    • How to Construct Sufficient Conditions for Hash Functions, by Yu Sasaki, Yusuke Naito, Jun Yajima, Takeshi Shimoyama, Noboru Kunihiro, and Kazuo Ohta,
      in Proc. of Vietcrypt2006, LNCS4341, pp. 115-130,September 25-28, 2006, Hanoi, Vietnam.
    • Provable Secure Electronic Cash based on Blind Multisignature schemes, by Y. Hanatani, Y. Komano, K. Ohta and N. Kunihiro, in Financial Cryptography'06, LNCS 4107, pp. 236-250, Feb.27-March 2, 2006, Anguilla.
  • 2005
    • Improved Collision Attack on MD4 with Probability Almost 1, by Y. Naito, Y. Sasaki, N. Kunihiro and K. Ohta
      In 8th ICISC, LNCS 3935, pp. 129-145, Dec. 1-2, 2005, Seoul, Korea.
    • Analysis on the Clockwise Transposition Routing for Dedicated Factoring Devices, by T. Izu, N. Kunihiro, K. Ohta and T. Shimoyama
      In WISA2005, August 22-24, pp. 232-242, 2005 Jeju Island, Korea.

Journal Papers (in English)

• 2009
  • Small Secret Key Attack on a Takagi's Variant of RSA, by Kouichi Itoh, Noboru Kunihiro and Kaoru Kurosawa,
    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E92-A, No.1, pp. 33-41, 2009.
  • Near-Collision Attacks on MD4: Applied to MD4-Based Protocols, by Lei Wang, Kazuo Ohta and Noboru Kunihiro,
    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E92-A, No.1, pp. 76-86, 2009.
  • A Strict Evaluation on the Number of Conditions for SHA-1 Collision Search, by Jun Yajima, Terutoshi Iwasaki, Yusuke Naito, Yu Sasaki, Takeshi Shimoyama, Thomas Peyrin, Noboru Kunihiro and Kazuo Ohta,
    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E92-A, No.1, pp. 87-95, 2009.
  • Extended Password Recovery Attacks against APOP, SIP, and Digest Authentication, by Yu Sasaki, Lei Wang, Kazuo Ohta and Noboru Kunihiro,
    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E92-A, No.1, pp. 96-104, 2009.
• 2008
  • Deterministic Polynomial Time Equivalence between Factoring and Key-Recovery Attack on Takagi's RSA, by Noboru Kunihiro and Kaoru Kurosawa,
    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E91-A, No.9, pp. 2356-2364, 2008.
  • A Fast Quantum Circuit for Addition with Few Qubits, by Yasuhiro Takahashi and Noboru Kunihiro,
    Quantum Information and Computation, Vol.8 No.6/7, pp.636-649, 2008.
  • Improved Collision Search for Hash Functions: New Advanced Message Modification, by Yusuke NAITO Kazuo OHTA Noboru KUNIHIRO,
    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E91-A, No.1, pp. 46-54, 2008.
  • New Message Differences for Collision Attacks on MD4 and MD5, by Yu SASAKI Lei WANG Noboru KUNIHIRO Kazuo OHTA,
    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E91-A, No.1, pp. 55-63, 2008.
  • Factorization of Square-Free Integers with High Bits Known, by Bagus SANTOSO Noboru KUNIHIRO Naoki KANAYAMA Kazuo OHTA,
    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E91-A, No.1, pp. 306-315, 2008.
• 2007
  • Provably Secure Untraceable Electronic Cash against Insider Attacks, by Y. Hanatani, Y. Komano, K. Ohta and N. Kunihiro,
    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E90-A, No.5, pp. 980-991, 2007.
  • The quantum Fourier transform on a linear nearest neighbor architecture, by Yasuhiro Takahashi, Noboru Kunihiro and Kazuo Ohta,
    Quantum Information and Computation, Vol.7 No.4, pp.383-391, 2007.
  • Improved Collision Attacks on MD4 and MD5, by Y. SASAKI, Y. NAITO, N. KUNIHIRO and Kazuo OHTA
    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E90-A, No.1, pp. 36-47, 2007.
• 2006
  • Maurer-Yacobi ID based Key Distribution Revisited, by N. Kunihiro W. Abe and K. Ohta,
    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E89-A, No.5, pp. 1421-1424, 2006.
  • Visual Secret Sharing Schemes for Multiple Secret Images Allowing the Rotation of Shares, by M. Iwamoto, L. Wang, K. Yoneyama, N. Kunihiro and K. Ohta,
    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E89-A, No.5, pp. 1382-1395, 2006.
  • A quantum circuit for Shor's factoring algorithm using 2n+2 qubits, by Yasuhiro Takahashi and Noboru Kunihiro,
    Quantum Information and Computation, Vol.6 No.2, pp.184-192, 2006.
• 2005
  • A LINEAR-SIZE QUANTUM CIRCUIT FOR ADDITION WITH NO ANCILLARY QUBITS, by Yasuhiro Takahashi and Noboru Kunihiro,
    Quantum Information and Computation, Vol.5 No.6, pp.440-448, 2005.
  • Exact Analyses of Computational Time for Factoring in Quantum Computers, by N. Kunihiro
    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E88-A, No.1, pp. 105-111, 2005.
• -2004
  • Efficient Algorithms for NMR Quantum Computers with Small Qubits, by Noboru KUNIHIRO and Shigeru YAMASHITA
    New Generation Computing Vol. 21, No. 4, pp.329-337, 2003.
  • A Quantum Algorithm using NMR Computers to Break Secret-Key Cryptosystems, by Kazuo OHTA, Tetsuro NISHINO, Seiya OKUBO and Noboru KUNIHIRO
    New Generation Computing Vol. 21, No. 4, pp.347-361, 2003.
  • Cryptographic Works of Dr. Kenji Koyama: In Memoria, by Kunihiro, N., Ohta K., Okamoto T., Terada R., and Tsuruoka Y.
    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E84-A, No.1, pp. 108-113, 2001.
  • Two Discrete Log Algorithms for Super-Anomalous Elliptic Curves and Their Applications, by Kunihiro, N. and Koyama, K.
    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E83-A, No.1, pp. 10-16, 2000.
  • New methods for generating short addition chains, by Kunihiro, N. and Yamamoto, H
    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E83-A, No.1, pp. 60-67, 2000.
  • Window and Extended Window methods for Additon chain and Addition-Subtraction chain, by Kunihiro, N. and Yamamoto, H.
    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, Vol. E81-A, No.1, pp. 72-81, 1998.

Program Committee:

• IWSEC2010 Program co-Chair (2010.11)
• ProvSec2010 Program Committee (2010.10)
• IWSEC2009 Program Committee (2009.10)
• ISITA2008 Technical Program Committee (2008.12)
• IWSEC2008 Program Committee (2008.11)
• IWSEC2007 Program Committee (2007.10)
• TQC2007 Program Committee (2007.01)
• IWSEC2006 Program Committee (2006.10)
• ISITA2006 Technical Program Committee (2006.10)
• TQC2006 Program Committee (2006.02)
• 3rd International IEEE Security in Storage Workshop Program Committee (2005.12)
• ISITA2004 Technical Program Committee (2004.10)

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