Christoph Dobraunig

Research Scientist

Biography

Currently, I am working for Intel. Before that, I worked for Lamarr Security Research, the Radboud University in Nijmegen, and the Graz University of Technology. So far, I have done research in cryptography (analysis and design of symmetric cryptography) and implementation security (side-channel and fault attacks). However, my interests are not limited to these topics. I am a co-designer of the authenticated encryption schemes Ascon, Elephant, and ISAP. Moreover, I am part of the SPHINCS⁺ Team.

Interests

Cryptography
Information Security
Implementation Security

Education

Doctoral Programme in Computer Sciences, 2014–2017

Graz University of Technology
Master's Programme in Telematics (Information and Computer Engineering), 2011–2014

Graz University of Technology
Bachelor's Programme in Telematics (Information and Computer Engineering), 2007–2011

Graz University of Technology

Journal Articles

Christoph Dobraunig, Maria Eichlseder, Florian Mendel, Martin Schläffer. Ascon v1.2: Lightweight Authenticated Encryption and Hashing. Journal of Cryptology, 2021.

Christoph Dobraunig, Bart Mennink. Tightness of the Suffix Keyed Sponge Bound. In IACR Transactions on Symmetric Cryptology, 2020.

Joan Daemen, Christoph Dobraunig, Maria Eichlseder, Hannes Gross, Florian Mendel, Robert Primas. Protecting against Statistical Ineffective Fault Attacks. In IACR Transactions on Cryptographic Hardware and Embedded Systems, 2020.

PDF Code Preprint

Christoph Dobraunig, Yann Rotella, Jan Schoone. Algebraic and Higher-Order Differential Cryptanalysis of Pyjamask-96. In IACR Transactions on Symmetric Cryptology, 2020.

Christoph Dobraunig, Maria Eichlseder, Stefan Mangard, Florian Mendel, Bart Mennink, Robert Primas, Thomas Unterluggauer. ISAP v2.0. In IACR Transactions on Symmetric Cryptology Special Issue, 2020.

PDF Code Video Website

Tim Beyne, Yu Long Chen, Christoph Dobraunig, Bart Mennink. Dumbo, Jumbo, and Delirium: Parallel Authenticated Encryption for the Lightweight Circus. In IACR Transactions on Symmetric Cryptology Special Issue, 2020.

PDF Code Website

Christoph Dobraunig, Florian Mendel, Bart Mennink. Practical Forgeries for ORANGE. In Information Processing Letters, 2020.

Gaoli Wang, Fukang Liu, Binbin Cui, Florian Mendel, Christoph Dobraunig. Improved (semi-free-start/near-) collision and distinguishing attacks on round-reduced RIPEMD-160. In Designs, Codes and Cryptography, 2020.

Christoph Dobraunig, Farokhlagha Moazami, Christian Rechberger, Hadi Soleimany. Framework for faster key search using related-key higher-order differential properties: applications to Agrasta. In IET Information Security, 2020.

Christoph Dobraunig, Bart Mennink. Security of the Suffix Keyed Sponge. In IACR Transactions on Symmetric Cryptology, 2019.

Fukang Liu, Christoph Dobraunig, Florian Mendel, Takanori Isobe, Gaoli Wang, Zhenfu Cao. New Semi-Free-Start Collision Attack Framework for Reduced RIPEMD-160. In IACR Transactions on Symmetric Cryptology, 2019.

Ralph Ankele, Christoph Dobraunig, Jian Guo, Eran Lambooij, Gregor Leander, Yosuke Todo. Zero-Correlation Attacks on Tweakable Block Ciphers with Linear Tweakey Expansion. In IACR Transactions on Symmetric Cryptology, 2019.

Christoph Dobraunig, Maria Eichlseder, Thomas Korak, Stefan Mangard, Florian Mendel, Robert Primas. SIFA: Exploiting Ineffective Fault Inductions on Symmetric Cryptography. In IACR Transactions on Cryptographic Hardware and Embedded Systems, 2018.

Christoph Dobraunig, Maria Eichlseder, Stefan Mangard, Florian Mendel, Thomas Unterluggauer. ISAP - Towards Side-Channel Secure Authenticated Encryption. In IACR Transactions on Symmetric Cryptology, 2017.

Hannes Groß, Erich Wenger, Christoph Dobraunig, Christoph Ehrenhöfer. Ascon hardware implementations and side-channel evaluation. In Microprocessors and Microsystems - Embedded Hardware Design 52, 2017.

Christoph Dobraunig, Maria Eichlseder, Daniel Kales, Florian Mendel. Practical Key-Recovery Attack on MANTIS 5. In IACR Transactions on Symmetric Cryptology, 2016.

Conference & Workshop Papers

Christoph Dobraunig, Lorenzo Grassi, Anna Guinet, Daniël Kuijsters. Ciminion: Symmetric Encryption Based on Toffoli-Gates over Large Finite Fields. In EUROCRYPT, 2021.

Christoph Dobraunig, Bart Mennink. Leakage Resilient Value Comparison With Application to Message Authentication. In EUROCRYPT, 2021.

Christoph Dobraunig, Bart Mennink. Leakage Resilience of the Duplex Construction. In ASIACRYPT, 2019.

Christoph Dobraunig, Maria Eichlseder, Florian Mendel, Markus Schofnegger. Algebraic Cryptanalysis of Variants of Frit. In SAC, 2019.

Fukang Liu, Christoph Dobraunig, Florian Mendel, Takanori Isobe, Gaoli Wang, Zhenfu Cao. Efficient Collision Attack Frameworks for RIPEMD-160. In CRYPTO, 2019.

PDF Video Preprint

Christoph Dobraunig, Maria Eichlseder, Hannes Gross, Stefan Mangard, Florian Mendel, Robert Primas. Statistical Ineffective Fault Attacks on Masked AES with Fault Countermeasures. In ASIACRYPT, 2018.

Christoph Dobraunig, Maria Eichlseder, Lorenzo Grassi, Virginie Lallemand, Gregor Leander, Eik List, Florian Mendel, Christian Rechberger. Rasta: A cipher with low ANDdepth and few ANDs per bit. In CRYPTO, 2018.

PDF Code Video Preprint

Christoph Dobraunig, Stefan Mangard, Florian Mendel, Robert Primas. Fault Attacks on Nonce-based Authenticated Encryption: Application to Keyak and Ketje. In SAC, 2018.

Christoph Dobraunig, Maria Eichlseder, Thomas Korak, Florian Mendel. Side-Channel Analysis of Keymill. In COSADE, 2017.

Christoph Dobraunig, Eik List. Impossible-Differential and Boomerang Cryptanalysis of Round-Reduced Kiasu-BC. In CT-RSA, 2017.

Christoph Dobraunig, Maria Eichlseder, Thomas Korak, Victor Lomné, Florian Mendel. Statistical Fault Attacks on Nonce-Based Authenticated Encryption Schemes. In ASIACRYPT, 2016.

PDF Video Preprint

Christoph Dobraunig, Maria Eichlseder, Florian Mendel. Cryptanalysis of Simpira v1. In SAC, 2016.

Christoph Dobraunig, Maria Eichlseder, Florian Mendel. Square Attack on 7-Round Kiasu-BC. In ACNS, 2016.

Christoph Dobraunig, Maria Eichlseder, Florian Mendel. Analysis of the Kupyna-256 Hash Function. In FSE, 2016.

Christoph Dobraunig, Maria Eichlseder, Florian Mendel. Analysis of SHA-512/224 and SHA-512/256. In ASIACRYPT, 2015.

Christoph Dobraunig, Maria Eichlseder, Florian Mendel. Heuristic Tool for Linear Cryptanalysis with Applications to CAESAR Candidates. In ASIACRYPT, 2015.

PDF Code Preprint

Christoph Dobraunig, Maria Eichlseder, Florian Mendel. Higher-Order Cryptanalysis of LowMC. In ICISC, 2015.

Christoph Dobraunig, François Koeune, Stefan Mangard, Florian Mendel, François-Xavier Standaert. Towards Fresh and Hybrid Re-Keying Schemes with Beyond Birthday Security. In CARDIS, 2015.

Christoph Dobraunig, Maria Eichlseder, Florian Mendel. Forgery Attacks on Round-Reduced ICEPOLE-128. In SAC, 2015.

Hannes Groß, Erich Wenger, Christoph Dobraunig, Christoph Ehrenhöfer. Suit up! - Made-to-Measure Hardware Implementations of Ascon. In DSD, 2015.

Christoph Dobraunig, Maria Eichlseder, Florian Mendel, Martin Schläffer. Cryptanalysis of Ascon. In CT-RSA, 2015.

Christoph Dobraunig, Maria Eichlseder, Florian Mendel. Related-Key Forgeries for Prøst-OTR. In FSE, 2015.

Christoph Dobraunig, Maria Eichlseder, Stefan Mangard, Florian Mendel. On the Security of Fresh Re-keying to Counteract Side-Channel and Fault Attacks. In CARDIS, 2014.

Andrey Bogdanov, Christoph Dobraunig, Maria Eichlseder, Martin M. Lauridsen, Florian Mendel, Martin Schläffer, Elmar Tischhauser. Key Recovery Attacks on Recent Authenticated Ciphers. In LATINCRYPT, 2014.

Christoph Dobraunig, Florian Mendel, Martin Schläffer. Differential Cryptanalysis of SipHash. In SAC, 2014.

Thomas Plos, Christoph Dobraunig, Markus Hofinger, Alexander Oprisnik, Christoph Wiesmeier, Johannes Wiesmeier. Compact Hardware Implementations of the Block Ciphers mCrypton, NOEKEON, and SEA. In INDOCRYPT, 2012.

Other Publications

Christoph Dobraunig, Maria Eichlseder, Florian Mendel, Martin Schläffer. Ascon. NIST Finalist, 2021.

PDF Code Project Source Document Website

Tim Beyne, Yu Long Chen, Christoph Dobraunig, Bart Mennink. Elephant. NIST Finalist, 2021.

PDF Code Project Source Document Website

Christoph Dobraunig, Maria Eichlseder, Stefan Mangard, Florian Mendel, Bart Mennink, Robert Primas, Thomas Unterluggauer. ISAP. NIST Finalist, 2021.

PDF Code Project Source Document Website

Christoph Dobraunig, Bart Mennink, Robert Primas. Exploring the Golden Mean Between Leakage and Fault Resilience and Practice. eprint, 2020.

Jean-Philippe Aumasson, Daniel J. Bernstein, Christoph Dobraunig, Maria Eichlseder, Scott Fluhrer, Stefan-Lukas Gazdag, Andreas Hülsing, Panos Kampanakis, Stefan Kölbl, Tanja Lange, Martin M. Lauridsen, Florian Mendel, Ruben Niederhagen, Christian Rechberger, Joost Rijneveld, Peter Schwabe. SPHINCS+. Submission to the NIST Post-Quantum Cryptography Call, 2019.

PDF Source Document Website

Christoph Dobraunig, Maria Eichlseder, Florian Mendel. Security Evaluation of SHA-224, SHA-512/224, and SHA-512/256. Tech. Report CRYPTREC, 2014.

Christoph Dobraunig, Maria Eichlseder, Florian Mendel, Martin Schläffer. Ascon. CAESAR: first choice for lightweight applications (resource constrained environments), 2014.

PDF Code Project Website

Service

Program Committee

2021: EuroS&P, FSE
2020: EuroS&P, FSE
2019: FSE

External Reviewer

2020: ACNS, ASIACRYPT, CHES, CRYPTO, EUROCRYPT
2019: AFRICACRYPT, ASIACRYPT, CHES, IndoCrypt
2018: ACNS, ASIACRYPT, COSADE, EUROCRYPT, Inscrypt, IWSEC
2017: ASIACRYPT, EUROCRYPT, Inscrypt, SAC
2016: ACNS, ASIACRYPT, CRYPTO, FSE, ICISC, ICISSP, IndoCrypt, Inscrypt
2015: CHES, FSE, ICISC, IndoCrypt, Inscrypt, SAC
2014: ASIACRYPT, CHES, ICISC, INSCRYPT

Journal Reviewer

Designs, Codes and Cryptography; IEEE Transactions on Information Forensics & Security; IEEE Transactions on Very Large Scale Integration Systems; IET Information Security; Journal of Cryptographic Engineering; Journal of Cryptology; Journal of Mathematical Cryptology;

Talks

Nov. 2020, FSE, “Isap v2.0”, virtual, joint work with: M. Eichlseder, S. Mangard, F. Mendel, Bart Mennink, Robert Primas, and T. Unterluggauer.
Aug. 2019, CRYPTO, “Efficient Collision Attack Frameworks for RIPEMD-160”, Santa Barbara, USA, joint work with: F. Liu, F. Mendel, T. Isobe, G. Wang , and Z. Cao.
Oct. 2018, Permutation-based Cryptography, “On ASCON and ISAP”, Milan, Italy, based on joint work with: M. Eichlseder, S. Mangard, F. Mendel, M. Schläffer, and T. Unterluggauer.
Sep. 2018, Simula UiB, “Statistical (Ineffective) Fault Attacks”, Bergen, Norway, based on joint work with: M. Eichlseder, H. Groß, T. Korak, V. Lomné, S. Mangard, F. Mendel, R. Primas.
Sep. 2018, Rump Session at CHES, “SIFA: Statistical Ineffective Fault Attacks”, Amsterdam, Netherlands, based on joint work with: M. Eichlseder, H. Groß, T. Korak, S. Mangard, F. Mendel, R. Primas.
Sep. 2018, Radboud University, “Statistical (Ineffective) Fault Attacks”, Nijmegen, Netherlands, based on joint work with: M. Eichlseder, H. Groß, T. Korak, Victor Lomné, S. Mangard, F. Mendel, R. Primas.
Aug. 2018, CRYPTO, “Rasta: A cipher with low ANDdepth and few ANDs per bit”, Santa Barbara, USA, joint work with: M. Eichlseder, L. Grassi, V. Lallemand, G. Leander, E. List, F. Mendel, and C. Rechberger.
Aug. 2018, Rump Session at CRYPTO, “SIFA: Statistical Ineffective Fault Attacks”, Santa Barbara, USA, based on joint work with: M. Eichlseder, H. Groß, T. Korak, S. Mangard, F. Mendel, R. Primas.
Jan. 2018, Joanneum Research, “On Side-channel and Fault Attacks”, Klagenfurt, Austria, based on joint work with: M. Eichlseder, T. Korak, V. Lomné, S. Mangard, F. Mendel, and T. Unterluggauer.
Jan. 2018, Dagstuhl Seminar, “Rasta: Designing a cipher with low ANDdepth and few ANDs per bit”, Dagstuhl, Germany, joint work with: M. Eichlseder, L. Grassi, V. Lallemand, G. Leander, F. Mendel, and C. Rechberger.
Apr. 2017, COSADE, “Side-Channel Analysis of Keymill”, Paris, France, joint work with: M. Eichlseder, T. Korak, and F. Mendel.
Mar. 2017, COST, “ISAP: Towards Side-channel Secure AE”, Amsterdam, Netherlands, joint work with: M. Eichlseder, S. Mangard, F. Mendel, and T. Unterluggauer.
Mar. 2017, FSE, “ISAP: Towards Side-channel Secure AE”, Tokyo, Japan, joint work with: M. Eichlseder, S. Mangard, F. Mendel, and T. Unterluggauer.
Jan. 2017, ESC, “ISAP: Towards Side-channel Secure AE”, Luxembourg, Luxembourg, joint work with: M. Eichlseder, S. Mangard, F. Mendel, and T. Unterluggauer.
Dec. 2016, ASIACRYPT, “Statistical Fault Attacks on Nonce-Based Authenticated Encryption Schemes”, Hanoi, Vietnam, joint work with: M. Eichlseder, T. Korak, V. Lomné, and F. Mendel.
June 2016, ACNS, “Square Attack on 7-Round Kiasu-BC”, Guildford, UK, joint work with: M. Eichlseder, and F. Mendel.
Dec. 2015, ASIACRYPT, “Heuristic Tool for Linear Cryptanalysis with Applications to CAESAR Candidates”, Auckland, New Zealand, joint work with: M. Eichlseder, and F. Mendel.
Aug. 2015, SAC, “Forgery Attacks on Round-Reduced ICEPOLE-128”, Sackville, Canada, joint work with: M. Eichlseder, and F. Mendel.
Jul. 2015, CECC, “Ascon: A Submission to CAESAR”, Klagenfurt, Austria, joint work with: M. Eichlseder, F. Mendel, and M. Schläffer.
Apr. 2015, CT-RSA, “Analysis of Ascon”, San Francisco, USA, joint work with: M. Eichlseder, F. Mendel, and M. Schläffer.
Nov. 2014, CARDIS, “On the Security of Fresh Re-keying”, Paris, France, joint work with: M. Eichlseder, S. Mangard, and F. Mendel.
Aug. 2014, SAC, “Differential Cryptanalysis of SipHash”, Montreal, Canada, joint work with: F. Mendel, and M. Schläffer.