Ruhr-University Bochum
Faculty of Computer Science
Symmetric Cryptography
Universitätsstr. 150
44801 Bochum
Room: MC 1.42
Tel: +49 (0)234 32-28402
E-Mail: gregor.leander@rub.de
Office hours: By Arrangement
Table of Contents
Publications
Please consult my google scholar profile or my dblp entry for an up-to-date list of publications
Symetric Crypto@RUB
My primary field of research is cryptography, more precisely symmetric cryptography. Symmetric cryptographic primitives protect a large percentage of today’s data, whether in transit or storage. Symmetric cryptography spans a wide range from theoretic considerations to practical impact in real world applications and I am interested in working on all ends. On the one hand, having a background in mathematics and a PhD focused on theoretical aspects of Boolean functions, I have certainly an intrinsic interest in the fundamental questions in symmetric cryptography. On the other hand, I have been involved in the design of ciphers and seeing them deployed massively in products as well as breaking and fixing ciphers already deployed in practice is a great experience.
I created the symmetric cryptography group at the Ruhr University Bochum in 2015 and since then my group has become a great place for new ideas, approaches, and fruitful discussions. We have regular visits that are a great source of collaboration and chances for the PhD students to build and deepen their scientific networks
ToSC - IACR Transaction of Symmetric Cryptography
- I also like to mention that I am the founder and managing editor of the journal IACR Transaction of Symmetric Cryptography, that transformed the conference FSE into a conference/journal hybrid. I created this diamond open access journal, published by the Ruhr University Bochum, out of the strong belief that (i) it significantly improves the quality of the publications compared to a conference-only model and (ii) the fact that we write, review and layout the papers already does not justify the cost and business model of most of the professional publishers in the area.
Organisation of Scientific Meetings
- 2024 EUROCRYPT , Zurich , program co-chair
- 2022 Symmetric Cryptography Seminar, Dagstuhl, co-organizer
- 2020 Symmetric Cryptography Seminar, Dagstuhl, co-organizer
- 2019 FrisiaCrypt, Borkum, general co-chair
- 2018 Symmetric Cryptography Seminar, Dagstuhl, co-organizer
- 2016 Fast Software Encryption, Bochum, general chair
- 2015 Fast Software Encryption, Istanbul, program chair
- 2014 EUROCRYPT , Copenhagen , general co-chair
- 2011 Workshop on Lightweight Cryptography, program co-chair
- 2011 Fast Software Encryption, Copenhagen , general co-chair
- 2011 Symmetric Key Encryption Workshop, general and program co-chair
Invited Talks
- Indocrypt 2022
- Santacrypt 2022
- IACR FSE 2019
- CTCRYPT 2017
- MMCC 2017
- Arcticrypt 2016
- China Crypt 2016
- Rumanian Crypto days 2015 and 2017
- SantaCrypt 2014
- LightSec 2013
- BalkanCrypt 2013
- WCC 2013
- Latincrypt 2012
Prizes and Awards
- 2022 SKINNY is ISO standard (ISO/IEC 18033-7) as a Tweakable Block Cipher
- 2020 IACR CRYPTO 2020, Best Paper Award and invitation to Journal of Cryptology
- 2015 Heisenberg Professorship, a prestigious funding line for upcoming leaders by the DFG.
- 2014 IACR FSE 2014, Best Paper Award and invitation to Journal of Cryptology
- 2010 PRESENT is ISO standard (ISO/IEC 29192-2) for Lightweight Cryptography
- 2010 German IT-Security Award (worth 100kEUR), first place
- 2011 Erdos Number 2
Teaching
see this page for a list of present and past courses.
Publications
2023
2022
2021
2020
2019
2018
2017
2016
2015
2014
2013
2012
2011
2010
2009
2008
2007
2006
2005
2004
2003
2001
Publications
McEliece Needs a Break - Solving McEliece-1284 and Quasi-Cyclic-2918 with Modern ISD
Andre Esser, Alexander May, Floyd Zweydinger
In: Advances in Cryptology (EUROCRYPT 22), S. 433–457, Springer, 2022.
Links | Schlagwörter: Crypto Flagship, Rank A*/A
@inproceedings{DBLP:conf/eurocrypt/EsserMZ22,
title = {McEliece Needs a Break - Solving McEliece-1284 and Quasi-Cyclic-2918 with Modern ISD},
author = {Andre Esser and Alexander May and Floyd Zweydinger},
url = {https://eprint.iacr.org/2021/1634.pdf, Paper
https://iacr.org/submit/files/slides/2022/eurocrypt/eurocrypt2022/109/slides.pdf, Slides
https://youtube.com/watch?v=nkRpkf4efuE, Video
https://doi.org/10.1007/978-3-031-07082-2_16, DOI},
year = {2022},
date = {2022-05-01},
urldate = {2022-05-01},
booktitle = {Advances in Cryptology (EUROCRYPT 22)},
volume = {13277},
pages = {433–457},
publisher = {Springer},
series = {Lecture Notes in Computer Science},
keywords = {Crypto Flagship, Rank A*/A},
pubstate = {published},
tppubtype = {inproceedings}
}
How Not to Protect Your IP - An Industry-Wide Break of IEEE 1735 Implementations
Julian Speith, Florian Schweins, Maik Ender, Marc Fyrbiak, Alexander May, Christof Paar
In: Symposium on Security and Privacy (S&P 22), 2022.
Links | Schlagwörter: Rank A*/A, Security
@inproceedings{DBLP:conf/sp/SpeithSEF0P22,
title = {How Not to Protect Your IP - An Industry-Wide Break of IEEE 1735 Implementations},
author = {Julian Speith and Florian Schweins and Maik Ender and Marc Fyrbiak and Alexander May and Christof Paar},
url = {https://arxiv.org/abs/2112.04838, Paper
https://www.youtube.com/watch?v=-xmWZgldab8, Video
https://doi.org/10.1109/SP46214.2022.9833605, DOI},
year = {2022},
date = {2022-04-01},
urldate = {2022-04-01},
booktitle = {Symposium on Security and Privacy (S&P 22)},
keywords = {Rank A*/A, Security},
pubstate = {published},
tppubtype = {inproceedings}
}
Legendre PRF (Multiple) Key Attacks and the Power of Preprocessing
Alexander May, Floyd Zweydinger
In: Computer Security Foundations Symposium (CSF 22), S. 428–438, IEEE, 2022.
Links | Schlagwörter: Rank A*/A, Security
@inproceedings{DBLP:conf/csfw/MayZ22,
title = {Legendre PRF (Multiple) Key Attacks and the Power of Preprocessing},
author = {Alexander May and Floyd Zweydinger},
url = {https://eprint.iacr.org/2021/645.pdf, Paper
https://informatik.rub.de/wp-content/uploads/2022/10/Slides-1.pdf, Slides
https://doi.org/10.1109/CSF54842.2022.9919640, DOI},
year = {2022},
date = {2022-01-01},
urldate = {2022-01-01},
booktitle = {Computer Security Foundations Symposium (CSF 22)},
pages = {428–438},
publisher = {IEEE},
keywords = {Rank A*/A, Security},
pubstate = {published},
tppubtype = {inproceedings}
}
Quantum Period Finding is Compression Robust
Alexander May, Lars Schlieper
In: Transactions on Symmetric Cryptology (TOSC 22), S. 183–211, 2022.
Links | Schlagwörter: Crypto Area, Quantum
@inproceedings{DBLP:journals/tosc/MayS22,
title = {Quantum Period Finding is Compression Robust},
author = {Alexander May and Lars Schlieper},
url = {https://arxiv.org/abs/1905.10074, Paper
https://2020.qcrypt.net/posters/QCrypt2020Poster013Schlieper.pdf, Poster
https://doi.org/10.46586/tosc.v2022.i1.183-211, DOI
https://dblp.uni-trier.de/rec/journals/tosc/MayS22.html?view=bibtex, bibtex},
year = {2022},
date = {2022-01-01},
urldate = {2022-01-01},
booktitle = {Transactions on Symmetric Cryptology (TOSC 22)},
journal = {IACR Trans. Symmetric Cryptol.},
volume = {2022},
number = {1},
pages = {183–211},
keywords = {Crypto Area, Quantum},
pubstate = {published},
tppubtype = {inproceedings}
}
Partial Key Exposure Attack on Short Secret Exponent CRT-RSA
Alexander May, Julian Nowakowski, Santanu Sarkar
In: Advances in Cryptology (ASIACRYPT 21), S. 99–129, Springer, 2021.
Links | Schlagwörter: Crypto Flagship, Rank A*/A
@inproceedings{DBLP:conf/asiacrypt/MayNS21,
title = {Partial Key Exposure Attack on Short Secret Exponent CRT-RSA},
author = {Alexander May and Julian Nowakowski and Santanu Sarkar},
url = {https://eprint.iacr.org/2021/972.pdf, Paper
https://iacr.org/submit/files/slides/2021/asiacrypt/asiacrypt2021/29/slides.pdf, Slides
https://youtube.com/watch?v=ibdS6JXSmTg, Video
https://doi.org/10.1007/978-3-030-92062-3_4, DOI},
year = {2021},
date = {2021-12-01},
urldate = {2021-12-01},
booktitle = {Advances in Cryptology (ASIACRYPT 21)},
volume = {13090},
pages = {99–129},
publisher = {Springer},
series = {Lecture Notes in Computer Science},
keywords = {Crypto Flagship, Rank A*/A},
pubstate = {published},
tppubtype = {inproceedings}
}
How to Meet Ternary LWE Keys
Alexander May
In: Advances in Cryptology (CRYPTO 21) , S. 701–731, Springer, 2021.
Links | Schlagwörter: Crypto Flagship, Rank A*/A
@inproceedings{may:21:crypto,
title = {How to Meet Ternary LWE Keys},
author = {Alexander May},
url = {https://eprint.iacr.org/2021/216.pdf, Paper
https://informatik.rub.de/wp-content/uploads/2024/03/how_to_meet_ternary.pdf, Slides
https://www.youtube.com/watch?v=Fa6PxC5ufvU, Video
https://link.springer.com/chapter/10.1007/978-3-030-84245-1_24, DOI},
year = {2021},
date = {2021-08-01},
urldate = {2021-08-01},
booktitle = {Advances in Cryptology (CRYPTO 21) },
pages = {701--731},
publisher = {Springer},
keywords = {Crypto Flagship, Rank A*/A},
pubstate = {published},
tppubtype = {inproceedings}
}
How to Find Ternary LWE Keys Using Locality Sensitive Hashing
Elena Kirshanova, Alexander May
In: Cryptography and Coding (IMACC 21), S. 247–264, Springer, 2021.
Links | Schlagwörter: Crypto Others
@inproceedings{DBLP:conf/ima/KirshanovaM21,
title = {How to Find Ternary LWE Keys Using Locality Sensitive Hashing},
author = {Elena Kirshanova and Alexander May},
url = {https://eprint.iacr.org/2021/1255.pdf, Paper
https://crypto-kantiana.com/elena.kirshanova/talks/IMACC21.pdf, Slides
https://doi.org/10.1007/978-3-030-92641-0_12, DOI},
year = {2021},
date = {2021-01-01},
urldate = {2021-01-01},
booktitle = {Cryptography and Coding (IMACC 21)},
volume = {13129},
pages = {247–264},
publisher = {Springer},
series = {Lecture Notes in Computer Science},
keywords = {Crypto Others},
pubstate = {published},
tppubtype = {inproceedings}
}
Noisy Simon Period Finding
Alexander May, Lars Schlieper, Jonathan Schwinger
In: Cryptographers' Track at the RSA Conference (CT-RSA 21), S. 75–99, Springer, 2021.
Links | Schlagwörter: Crypto Others, Quantum
@inproceedings{DBLP:conf/ctrsa/0001SS21,
title = {Noisy Simon Period Finding},
author = {Alexander May and Lars Schlieper and Jonathan Schwinger},
url = {https://www.arxiv.org/abs/1910.00802, Paper
https://simons.berkeley.edu/sites/default/files/docs/15461/lsn.pdf, Slides
https://2020.qcrypt.net/posters/QCrypt2020Poster014Schlieper.pdf, Poster
https://doi.org/10.1007/978-3-030-75539-3_4, DOI},
year = {2021},
date = {2021-01-01},
urldate = {2021-01-01},
booktitle = {Cryptographers' Track at the RSA Conference (CT-RSA 21)},
volume = {12704},
pages = {75–99},
publisher = {Springer},
series = {Lecture Notes in Computer Science},
keywords = {Crypto Others, Quantum},
pubstate = {published},
tppubtype = {inproceedings}
}
Towards Quantum Large-Scale Password Guessing on Real-World Distributions
Markus Dürmuth, Maximilian Golla, Philipp Markert, Alexander May, Lars Schlieper
In: Cryptology and Network Security (CANS 21), S. 412–431, Springer, 2021.
Links | Schlagwörter: Quantum, Security
@inproceedings{DBLP:conf/cans/DurmuthGMMS21,
title = {Towards Quantum Large-Scale Password Guessing on Real-World Distributions},
author = {Markus Dürmuth and Maximilian Golla and Philipp Markert and Alexander May and Lars Schlieper},
url = {https://eprint.iacr.org/2021/1299.pdf, Paper
https://maximiliangolla.com/files/2021/slides/cans21-51-quantum-pw-cracking_slides.pdf, Slides
https://doi.org/10.1007/978-3-030-92548-2_22, DOI},
year = {2021},
date = {2021-01-01},
urldate = {2021-01-01},
booktitle = {Cryptology and Network Security (CANS 21)},
volume = {13099},
pages = {412–431},
publisher = {Springer},
series = {Lecture Notes in Computer Science},
keywords = {Quantum, Security},
pubstate = {published},
tppubtype = {inproceedings}
}
Quantum Key Search for Ternary LWE
(Hrsg.)
Lecture Notes in Computer Science Bd. 12841, 2021, besucht am: 01.01.2021.
Links | Schlagwörter: Crypto Others, Quantum
@periodical{DBLP:conf/pqcrypto/HoofKM21,
title = {Quantum Key Search for Ternary LWE},
author = {Iggy Hoof and Elena Kirshanova and Alexander May},
url = {https://eprint.iacr.org/2021/865.pdf, Paper
https://pqcrypto2021.kr/download/program/1.3.1_presentation_qlwe(1).pdf, Slides
https://doi.org/10.1007/978-3-030-81293-5_7, DOI},
year = {2021},
date = {2021-01-01},
urldate = {2021-01-01},
booktitle = {Post-Quantum Cryptography (PQCrypto 21) },
volume = {12841},
pages = {117–132},
publisher = {Springer},
series = {Lecture Notes in Computer Science},
keywords = {Crypto Others, Quantum},
pubstate = {published},
tppubtype = {periodical}
}
Lectures (Moodle/Notes)
- Cryptanalysis (Codes, Classic 1, Cl. 2)
- Cryptography (Sym, Asym)
- Probabilistic (Basic, Algos)
- Quantum Algorithms (Script)
Former PhDs
Show names, year of graduation
- Önder Askin, 2024
- Floyd Zweydinger, 2023
- Lars Schlieper, 2022
- Alexander Helm, 2020
- Andre Esser, 2020
- Matthias Minihold, 2019
- Leif Both, 2018
- Robert Kübler, 2018
- Elena Kirshanova, 2016
- Ilya Ozerov, 2016
- Gottfried Herold, 2014
- Alexander Meurer, 2014
- Mathias Herrmann, 2011
- Maike Ritzenhofen, 2010
Calvin & Hobbes
Prof. Dr. Gregor Leander
Symmetric Cryptography
Professor / Head of Chair
Address:
Ruhr-University Bochum
Faculty of Computer Science
Symmetric Cryptography
Universitätsstr. 150
--D-44801 Bochum
Room: MC 1/42
Telephone: +49(0)234 32 28402
Office Hours: By arrangement
E-Mail: gregor.leander(at)rub.de
Publications
Please consult my google scholar profile or my dblp entry for an up-to-date list of publications
Symmetric Crypto@RUB
My primary field of research is cryptography, more precisely symmetric cryptography. Symmetric cryptographic primitives protect a large percentage of today’s data, whether in transit or storage. Symmetric cryptography spans a wide range from theoretic considerations to practical impact in real world applications and I am interested in working on all ends. On the one hand, having a background in mathematics and a PhD focused on theoretical aspects of Boolean functions, I have certainly an intrinsic interest in the fundamental questions in symmetric cryptography. On the other hand, I have been involved in the design of ciphers and seeing them deployed massively in products as well as breaking and fixing ciphers already deployed in practice is a great experience.
I created the symmetric cryptography group at the Ruhr University Bochum in 2015 and since then my group has become a great place for new ideas, approaches, and fruitful discussions. We have regular visits that are a great source of collaboration and chances for the PhD students to build and deepen their scientific networks.
ToSC - IACR Transaction of Symmetric Cryptography
I also like to mention that I am the founder and managing editor of the journal IACR Transaction of Symmetric Cryptography, that transformed the conference FSE into a conference/journal hybrid. I created this diamond open access journal, published by the Ruhr University Bochum, out of the strong belief that (i) it significantly improves the quality of the publications compared to a conference-only model and (ii) the fact that we write, review and layout the papers already does not justify the cost and business model of most of the professional publishers in the area.
Organisation of Scientific Meetings
- 2024 EUROCRYPT , Zurich , program co-chair
- 2022 Symmetric Cryptography Seminar, Dagstuhl, co-organizer
- 2020 Symmetric Cryptography Seminar, Dagstuhl, co-organizer
- 2019 FrisiaCrypt, Borkum, general co-chair
- 2018 Symmetric Cryptography Seminar, Dagstuhl, co-organizer
- 2016 Fast Software Encryption, Bochum, general chair
- 2015 Fast Software Encryption, Istanbul, program chair
- 2014 EUROCRYPT , Copenhagen , general co-chair
- 2011 Workshop on Lightweight Cryptography, program co-chair
- 2011 Fast Software Encryption, Copenhagen , general co-chair
- 2011 Symmetric Key Encryption Workshop, general and program co-chair
Invited Talks
- Indocrypt 2022
- Santacrypt 2022
- IACR FSE 2019
- CTCRYPT 2017
- MMCC 2017
- Arcticrypt 2016
- China Crypt 2016
- Rumanian Crypto days 2015 and 2017
- SantaCrypt 2014
- LightSec 2013
- BalkanCrypt 2013
- WCC 2013
- Latincrypt 2012
Prizes and Awards
- 2022 SKINNY is ISO standard (ISO/IEC 18033-7) as a Tweakable Block Cipher
- 2020 IACR CRYPTO 2020, Best Paper Award and invitation to Journal of Cryptology
- 2015 Heisenberg Professorship, a prestigious funding line for upcoming leaders by the DFG.
- 2014 IACR FSE 2014, Best Paper Award and invitation to Journal of Cryptology
- 2010 PRESENT is ISO standard (ISO/IEC 29192-2) for Lightweight Cryptography
- 2010 German IT-Security Award (worth 100kEUR), first place
- 2011 Erdos Number 2
Teaching
see this page for a list of present and past courses.