International Association
for Cryptologic Research

Cryptographic implementations are often vulnerable against physical attacks, fault injection analysis being among the most popular techniques. On par with development of attacks, the area of countermeasures is advancing rapidly, utilizing both hardware- and software-based approaches. When it comes to software encoding countermeasures for fault protection and their evaluation, there are very few proposals so far, mostly focusing on single operations rather than on cipher as a whole.

In this paper we propose an evaluation framework that can be used for analyzing the effectivity of software encoding countermeasures against fault attacks. We first formalize the encoding schemes in software, helping us to define what properties are required when designing a fault protection. These findings show that using anticodes in such countermeasure can increase its detection capabilities. We provide a way to generate a code according to user criteria and also a method to evaluate the level of protection of assembly implementations using encoding schemes. This evaluation is based on static code analysis and provides a practical information on how good will the protection be on a real device. Finally, we verify our findings by implementing a block cipher PRESENT, protected by encoding scheme based on anticodes, and provide a detailed evaluation of such implementation.

Towards advancing the use of BIG keys as a practical defense against key exfiltration, this paper provides efficiency improvements for cryptographic schemes in the bounded retrieval model (BRM). We identify probe complexity (the number of scheme accesses to the slow storage medium storing the big key) as the dominant cost. Our main technical contribution is what we call the large-alphabet subkey prediction lemma. It gives good bounds on the predictability under leakage of a random sequence of blocks of the big key, as a function of the block size. We use it to significantly reduce the probe complexity required to attain a given level of security. Together with other techniques, this yields security-preserving performance improvements for BRM symmetric encryption schemes and BRM public-key identification schemes.

We construct new four-party protocols for secure computation that are secure against a single malicious corruption. Our protocols can perform computations over a binary ring, and require sending just 1.5 ring elements per party, per gate. In the special case of Boolean circuits, this amounts to sending 1.5 bits per party, per gate. One of our protocols is robust, yet requires almost no additional communication. Our key technique can be viewed as a variant of the “dual execution” approach, but, because we rely on four parties instead of two, we can avoid any leakage, achieving the standard notion of security.

In this work, we propose a first version of an e-voting scheme that achieves end-to-end verifiability, everlasting privacy and efficient coercion resistance in the JCJ setting. Everlasting privacy is achieved assuming an anonymous channel, without resorting to dedicated channels between the election authorities to exchange private data. In addition, the proposed scheme achieves coercion resistance under standard JCJ assumptions. As a core building block of our scheme, we also propose a new primitive called publicly auditable conditional blind signature (PACBS), where a client receives a token from the signing server after interaction; the token is a valid signature only if a certain condition holds and the validity of the signature can only be checked by a designated verifier. We utilize this primitive to blindly mark votes under coercion in an auditable manner

Nowadays, RFID systems have earned an important place in our everyday lives. Its adoption is growing in areas where data security or privacy or both must be guaranteed. Since the RFID tag can be cloned, it is necessary to develop appropriate security solutions for these systems. Fortunately, many papers have proposed solutions for encryption or authentication. But it turns out that sometimes the proposal has security flaw or is too complicated for the RFID tag (which has very limited computing resources). In this paper we introduce a new authentication protocol using a new approach. Our proposal named R-MAC is well suited for RFID tags since it uses simple and lightweight constructions. R-MAC is at least as secure as the Mirror-Mac protocol introduced by Petros Mol et al.

Quantum computers are expected to have a dramatic impact on numerous fields, due to their anticipated ability to solve classes of mathematical problems much more efficiently than their classical counterparts. This particularly applies to domains involving integer factorisation and discrete logarithms, such as public key cryptography. In this paper we consider the threats a quantum-capable adversary could impose on Bitcoin, which currently uses the Elliptic Curve Digital Signature Algorithm (ECDSA) to sign transactions. We then propose a simple but slow commit-delay-reveal protocol, which allows users to securely move their funds from old (non-quantum-resistant) outputs to those adhering to a quantum-resistant digital signature scheme. The transition protocol functions even if ECDSA has already been compromised. While our scheme requires modifications to the Bitcoin protocol, these can be implemented as a soft fork.

In this work, we examine the feasibility of secure and undetectable point-to-point communication in a world where governments can read all the encrypted communications of their citizens. We consider a world where the only permitted method of communication is via a government-mandated encryption scheme, instantiated with government-mandated keys. Parties cannot simply encrypt ciphertexts of some other encryption scheme, because citizens caught trying to communicate outside the government's knowledge (e.g., by encrypting strings which do not appear to be natural language plaintexts) will be arrested. The one guarantee we suppose is that the government mandates an encryption scheme which is semantically secure against outsiders: a perhaps reasonable supposition when a government might consider it advantageous to secure its people's communication against foreign entities. But then, what good is semantic security against an adversary that holds all the keys and has the power to decrypt?

We show that even in the pessimistic scenario described, citizens can communicate securely and undetectably. In our terminology, this translates to a positive statement: all semantically secure encryption schemes support subliminal communication. Informally, this means that there is a two-party protocol between Alice and Bob where the parties exchange ciphertexts of what appears to be a normal conversation even to someone who knows the secret keys and thus can read the corresponding plaintexts. And yet, at the end of the protocol, Alice will have transmitted her secret message to Bob. Our security definition requires that the adversary not be able to tell whether Alice and Bob are just having a normal conversation using the mandated encryption scheme, or they are using the mandated encryption scheme for subliminal communication.

Our topics may be thought to fall broadly within the realm of steganography: the science of hiding secret communication within innocent-looking messages, or cover objects. However, we deal with the non-standard setting of an adversarially chosen distribution of cover objects (i.e., a stronger-than-usual adversary), and we take advantage of the fact that our cover objects are ciphertexts of a semantically secure encryption scheme to bypass impossibility results which we show for broader classes of steganographic schemes. We give several constructions of subliminal communication schemes under the assumption that key exchange protocols with pseudorandom messages exist (such as Diffie-Hellman, which in fact has truly random messages). Each construction leverages the assumed semantic security of the adversarially chosen encryption scheme, in order to achieve subliminal communication.

This paper proposes a simple single bit flip fault attack applicable to several LWE (Learning With Errors Problem) based lattice based schemes like KYBER, NEWHOPE, DILITHIUM and FRODO which were submitted as proposals for the NIST call for standardisation of post quantum cryptography. We have identified a vulnerability in the usage of nonce, during generation of secret and error components in the key generation procedure. Our fault attack, based on a practical bit flip model (single bit flip to very few bit flips for proposed parameter instantiations) enables us to retrieve the secret key from the public key in a trivial manner. We fault the nonce in order to maliciously use the same nonce to generate both the secret and error components which turns the LWE instance into an exactly defined set of linear equations from which the secret can be trivially solved for using Gaussian elimination.

We give a simple and efficient method for obfuscating pattern matching with wildcards. In other words, we construct a way to check an input against a secret pattern, which is described in terms of prescribed values interspersed with unconstrained “wildcard” slots. As long as the support of the pattern is sufficiently sparse and the pattern itself is chosen from an appropriate distribution, we prove that a polynomial-time adversary cannot find a matching input, except with negligible probability. We rely upon the generic group heuristic (in a regular group, with no multilinearity). Previous work provided less efficient constructions based on multilinear maps or LWE.

Event date: 8 August to 9 August 2018
Submission deadline: 20 April 2018
Notification: 10 June 2018

The New Zealand Institute for Security and Crime Science (NZISCS) aims to reduce crime and increase security through multi-disciplinary, evidence-based research, and builds on the global leadership of the Cyber Security Researchers of Waikato (CROW). As NZ’s first cyber security research programme, CROW created the NZ Cyber Security Challenge, and leads the Ministry of Business, Innovation and Employment funded STRATUS project (NZD12.2 mil). CROW collaborates with fifty other local and international organisations, including STRATUS end-user partners Interpol and NZ Police.

We are seeking to appoint a full time fixed term Research Fellow to contribute to our research objectives associated with cybercrime, computer security and cloud computing. This position has responsibilities to achieve research objectives associated with the STRATUS industry partners.

A PhD in cyber security, cybercrime, computer science or a related field is essential as is having demonstrated research ability in cyber security and cybercrime. A requirement of this position is the ability to commercialise research prototypes into products/services and the demonstrated ability to publish in high quality academic journals, work collaboratively with others and undertake some teaching if required. Preference will be given to candidates who have work experience with cybercrime, security, intelligence, or law enforcement agencies including work experience in the cybercrime, security digital forensics, machine learning, applied cryptography, etc. Salary will be in the range of NZ$74,034 to NZ$89,163 per year, depending on qualifications, skills and experience.

Enquiries of an academic nature should be sent to Assoc. Prof. Ryan Ko – Director, NZ Institute for Security and Crime Science, ryan.ko (at) waikato.ac.nz

Fixed-term until October 2020. Closing date: 16 March 2018 (NZ time) Vacancy number: 380090

Closing date for applications: 16 March 2018

Contact: Ryan Ko (ryan.ko AT waikato.ac.nz)

More information: http://www.jobs.waikato.ac.nz

The University of Waikato seeks applicants for the position of Aura Professor of Cyber Security.

Cyber security represents a large growth industry, which both tertiary and private sector organisations are collaborating on. The University of Waikato and NZ’s leading cyber security consultancy firm Aura information security are jointly seeking applicants for an exciting new position within the computer science faculty based in Hamilton. The Aura professor of cyber security will be expected to contribute to both the research and teaching programmes of the University, and in the research and consulting programme of Aura Information Security. The focus of the research programme for the University and Aura is in penetration testing, but expertise in other areas of cyber security (e.g. artificial intelligence and machine learning for cyber security, post-quantum cryptography, applied cryptography, cryptanalysis, etc) will also be helpful. This position will suit an ambitious academic with an outstanding teaching and research record and a strong interest in engagement with the cyber security industry, as well as research and development leaders in the cyber security industry who wishes to operate in an academic environment. Salary is negotiable.

Applications close 23 March 2018.

Closing date for applications: 23 March 2018

Contact: Ryan Ko (ryan.ko (at) waikato.ac.nz)

More information: https://www.waikato.ac.nz/vacancies/current-vacancies

Are you interested in joining a dynamic, inclusive, and growing applied cryptography start-up? Duality Technologies is an established funded start-up co-founded by experienced technology professionals including MIT professors, a Turing award winner, an experienced entrepreneur, members of the DARPA community and former technical leadership at RSA. We are commercializing encrypted computing technologies that address pressing unmet needs in the market, using techniques including homomorphic encryption, secure multi-party computation and more.

Duality Technologies is hiring a cryptographic engineer who has interest in developing and applying encrypted computing technologies. Implementation or prototyping experience is a plus, but not critical. The ideal candidate is a team player who is looking to grow with the company.

We are interested in candidates who have had exposure to a mixture of homomorphic encryption, secure multi-party computation, set intersection, functional encryption, cryptographic obfuscation and related techniques, but we don’t expect a successful candidate to have expertise in all of these areas.

We are interested in candidates at all levels from a fresh PhD graduate to experienced researchers / scientists / engineers. The candidate is expected to work some of the time from our office in Newark NJ. Occasional travel to other offices in Cambridge MA or Tel Aviv Israel is expected.

Requirements:

• A PhD in Computer Science, Computer Engineering, Applied Mathematics or a related field.

• Experience with modern encrypted computing technologies.

• An ability and willingness to work on a team.

Desired Skills:

• Experience with homomorphic encryption, lattice cryptography, secure multiparty computation or other encrypted computing technologies

• Experience implementing lattice cryptography in software or hardware

• Familiarity with C/C++, Java, Python

• Able to work in a dynamic, fast-paced environment

Closing date for applications: 31 December 2019

Contact: Kurt Rohloff, PhD.

CTO, Duality Technologies

krohloff (at) duality.cloud

More information: https://www.duality.cloud

The cryptography group at University of Salerno (ITALY) invites expressions of interest for post-doc positions in the field of privacy-preserving cryptography and distributed ledger technology, to be supervised by Ivan Visconti.

Candidates are expected to have a strong publication record (e.g., IACR conferences, CCS, IEEE S&P,....). The positions will be available soon.

Closing date for applications: 31 May 2018

Contact: Ivan Visconti, ivan.visconti (at) gmail.com

More information: https://sites.google.com/site/ivanvisconti/post-doc

The Cryptography Group and Cybersecurity Group work on a diverse range of topics, spanning from theoretical cryptography, protocols, and implementations/architecture/leakage, to large scale infrastructures and human aspects of security. Jointly the groups have 10 associated academics, nearly as many postdoctoral researchers, and 15 doctoral students. And we are expanding!

This advert is for:

S4 Compiler and Language based Leakage Mitigation: the aim of the studentship is to explore techniques by which programs written in standard C, or Assembly, can be augmented to include information about leakage sensitive variables with the aim of feeding this information down into the various compilation steps such that tools can insert mitigation strategies with minimal user interaction. The ideal candidate will have a strong background (or at least interest) in computer science (in particular languages and compilers), and some familiarity with side channel attacks.

Supervisor: Elisabeth Oswald

The studentship S4 supports EU/UK nationals with a tax-free stipend of around 22k GBP. The latest starting date for students is September 30th 2018.

You may apply for one, some, or all advertised studentships simultaneously (please explain your choice in your application). Your application needs to be filed via: http://www.bristol.ac.uk/study/postgraduate/apply/.

This advert has a nominal end date of 1.5.2018, but we will make appointments as soon as we have identified candidates with the right background.

Closing date for applications: 1 May 2018

Contact: Prof. Elisabeth Oswald, Elisabeth.Oswald (at) bristol.ac.uk

The Cryptography Group and Cybersecurity Group work on a diverse range of topics, spanning from theoretical cryptography, protocols, and implementations/architecture/leakage, to large scale infrastructures and human aspects of security. Jointly the groups have 10 associated academics, nearly as many postdoctoral researchers, and 15 doctoral students. And we are expanding!

This advert is for:

S3 Advancing Leakage Attacks: the aim of the studentship is to experiment with new and advanced techniques to utilise leakage, by e.g. blending it with traditional cryptanalysis, merging it with key ranking strategies, making it less dependent on statistical assumptions via investigation of non-parametric techniques etc. The ideal candidate will have a background in mathematics, or statistics, and cryptography.

Supervisor: Elisabeth Oswald

The studentship S3 supports EU/UK nationals with a tax-free stipend of around 22k GBP. The latest starting date for students is September 30th 2018.

You may apply for one, some, or all advertised studentships simultaneously (please explain your choice in your application). Your application needs to be filed via: http://www.bristol.ac.uk/study/postgraduate/apply/.

This advert has a nominal end date of 1.5.2018, but we will make appointments as soon as we have identified candidates with the right background.

Closing date for applications: 1 May 2018

Contact: Prof. Elisabeth Oswald, Elisabeth.Oswald (at) bristol.ac.uk

The Cryptography Group and Cybersecurity Group work on a diverse range of topics, spanning from theoretical cryptography, protocols, and implementations/architecture/leakage, to large scale infrastructures and human aspects of security. Jointly the groups have 10 associated academics, nearly as many postdoctoral researchers, and 15 doctoral students. And we are expanding!

This advert is for:

S2 Ranking Distinguishers: Modern side channel attack vectors offer increasingly sophisticated trade-offs between the trace complexity of distinguishers and the computational complexity of some associated key ranking procedure. The aim of the studentship is to determine how much computation is required to effectively recover a key using DPA by exploring computationally intensive distinguishers that reduce the cost of the enumeration phase. The ideal candidate will have a background in high performance computing, statistics, or cryptography.

Supervisors: Martijn Stam and Elisabeth Oswald

The studentship S2 supports UK nationals, who need to pass DV clearance, with a tax-free stipend of around 22k GBP. The latest starting date for students is September 30th 2018.

You may apply for one, some, or all advertised studentships simultaneously (please explain your choice in your application). Your application needs to be filed via: http://www.bristol.ac.uk/study/postgraduate/apply/.

This advert has a nominal end date of 1.5.2018, but we will make appointments as soon as we have identified candidates with the right background.

Closing date for applications: 1 May 2018

Contact: Martijn Stam, Martijn.Stam (at) bristol.ac.uk

The Cryptography Group and Cybersecurity Group work on a diverse range of topics, spanning from theoretical cryptography, protocols, and implementations/architecture/leakage, to large scale infrastructures and human aspects of security. Jointly the groups have 10 associated academics, nearly as many postdoctoral researchers, and 15 doctoral students. And we are expanding!

This advert is for:

S1: Usable Abstractions for Secure Programming - A Mental Models Approach: Cryptographic application programming interfaces (APIs) are currently widely used to provide security of communication and information flows in contemporary applications.  Existing research has highlighted that vulnerabilities arise in software due to misunderstanding about the guarantees provided by API functions or unintentional misconfiguration of relevant security parameters. However, little is understood about developers’ mental models that lead to such issues and the misalignment between these  models and the actual functionality the API as intended by developers. The aim of the studentship is to study developers’ mental models of security APIs and to understand any misalignment with correct API usage.  The ideal candidate will have a background in computer science (in particular programming languages) or software engineering and a strong interest in usable security.

Supervisors: Awais Rashid and Bogdan Warinschi

The studentship S1 supports UK nationals, who need to pass DV clearance, with a tax-free stipend of around 22k GBP. The latest starting date for students is September 30th 2018.

You may apply for one, some, or all four studentships simultaneously (please explain your choice in your application). Your application needs to be filed via: http://www.bristol.ac.uk/study/postgraduate/apply/.

This advert has a nominal end date of 1.5.2018, but we will make appointments as soon as we have identified candidates with the right background.

Closing date for applications: 1 May 2018

Contact: Prof. Awais Rashid, Awais.Rashid (at) bristol.ac.uk

Prof. Bogdan Warinschi, Bogdan.Warinschi (at) bristol.ac.uk

We give an efficient decision procedure that, on input two (acyclic) cryptographic expressions making arbitrary use of an encryption scheme and a (length doubling) pseudorandom generator, determines (in polynomial time) if the two expressions produce computationally indistinguishable distributions for any pseudorandom generator and encryption scheme satisfying the standard security notions of pseudorandomness and indistinguishability under chosen plaintext attack. The procedure works by mapping each expression to a symbolic pattern that captures, in a fully abstract way, the information revealed by the expression to a computationally bounded observer. We then prove that if any two (possibly cyclic) expressions are mapped to the same pattern, then the associated distributions are indistinguishable. At the same time, if the expressions are mapped to different symbolic patterns and do not contain encryption cycles, there are secure pseudorandom generators and encryption schemes for which the two distributions can be distinguished with overwhelming advantage.

Event date: 9 September to 12 September 2018
Submission deadline: 15 April 2018
Notification: 15 June 2018