Post-Quantum Cryptography: a Cryptanalysis Approach
Lead Research Organisation:
University of Birmingham
Department Name: School of Computer Science
Abstract
The security of many cryptographic protocols in use today relies on the computational hardness of mathematical problems such as integer factorization. These problems can be solved using quantum computers, and therefore most of our security infrastructures will become completely insecure once quantum computers are built. Post-quantum cryptography aims at developing security protocols that will remain secure even after quantum computers are built. The biggest security agencies in the world including GCHQ and the NSA (the American National Security Agency) have recommended a move towards post-quantum protocols, and the new generation of cryptographic standards will aim at post-quantum security.
Driven by the need to upgrade our cybersecurity infrastructures, many cryptographic algorithms have recently been developed which are claimed to offer post-quantum security. These proposals are based on a few distinct mathematical problems which are hoped to remain difficult for quantum computers, including lattice problems, multivariate polynomial system solving, coding theory problems, isogeny problems, and the security of cryptographic hash functions. Unfortunately, many of these problems, and more importantly the cryptographic algorithms that are built on top of them, have not been subject to a thorough security analysis yet, therefore leaving us with a risk to oversee major weaknesses in algorithms to be deployed in security applications.
In this fellowship, we will develop breakthrough cryptanalysis techniques to analyse the security of post-quantum cryptography candidate algorithms, and determine which algorithms may or may not be further considered for digital security applications. Using the insight gained through cryptanalysis, we will then develop new post-quantum cryptographic algorithms offering better security, efficiency and functionality properties in applications.
Driven by the need to upgrade our cybersecurity infrastructures, many cryptographic algorithms have recently been developed which are claimed to offer post-quantum security. These proposals are based on a few distinct mathematical problems which are hoped to remain difficult for quantum computers, including lattice problems, multivariate polynomial system solving, coding theory problems, isogeny problems, and the security of cryptographic hash functions. Unfortunately, many of these problems, and more importantly the cryptographic algorithms that are built on top of them, have not been subject to a thorough security analysis yet, therefore leaving us with a risk to oversee major weaknesses in algorithms to be deployed in security applications.
In this fellowship, we will develop breakthrough cryptanalysis techniques to analyse the security of post-quantum cryptography candidate algorithms, and determine which algorithms may or may not be further considered for digital security applications. Using the insight gained through cryptanalysis, we will then develop new post-quantum cryptographic algorithms offering better security, efficiency and functionality properties in applications.
People |
ORCID iD |
Christophe Petit (Principal Investigator / Fellow) |
Publications

Arpin S
(2024)
Finding orientations of supersingular elliptic curves and quaternion orders
in Designs, Codes and Cryptography

Beullens W
(2023)
Proving knowledge of isogenies: a survey
in Designs, Codes and Cryptography

Booher J
(2024)
Failing to Hash Into Supersingular Isogeny Graphs
in The Computer Journal

Booher J
(2022)
Failing to hash into supersingular isogeny graphs

Chen M
(2022)
On Fp-roots of the Hilbert class polynomial modulo p
in Journal of Mathematics (PRC)

Chen M
(2024)
SCALLOP-HD: group action from 2-dimensional isogenies

Description | New attacks and new designs of post-quantum cryptography protocols, based on isogenies and other assumptions |
Exploitation Route | Work has informed the design and selection of cryptographic algorithms One algorithm designed (SQIsignà is being considered for standardization. If standardized it will likely be used by millions of users and devices worldwide |
Sectors | Digital/Communication/Information Technologies (including Software) Government Democracy and Justice Security and Diplomacy |
URL | https://sqisign.org/ |
Description | Design and analysis of SQIsign, now considered for standardization by NIST |
First Year Of Impact | 2023 |
Sector | Digital/Communication/Information Technologies (including Software),Government, Democracy and Justice,Security and Diplomacy |
Impact Types | Economic Policy & public services |
Description | SQIsign algorithm design and submission to NIST |
Organisation | IBM |
Department | IBM Research Zurich |
Country | Switzerland |
Sector | Private |
PI Contribution | A digital signature algorithm was designed (bets paper award at Asiacrypt 2020) and later submitted to NIST as a candidate for standardization. The evaluation from NIST is still ongoing |
Collaborator Contribution | Design, implementation and analysis |
Impact | A digital signature algorithm was designed (bets paper award at Asiacrypt 2020) and later submitted to NIST as a candidate for standardization. The evaluation from NIST is still ongoing |
Start Year | 2020 |
Description | SQIsign algorithm design and submission to NIST |
Organisation | École normale supérieure de Lyon (ENS Lyon) |
Country | France |
Sector | Academic/University |
PI Contribution | A digital signature algorithm was designed (bets paper award at Asiacrypt 2020) and later submitted to NIST as a candidate for standardization. The evaluation from NIST is still ongoing |
Collaborator Contribution | Design, implementation and analysis |
Impact | A digital signature algorithm was designed (bets paper award at Asiacrypt 2020) and later submitted to NIST as a candidate for standardization. The evaluation from NIST is still ongoing |
Start Year | 2020 |