International Association for Cryptologic Research

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2014-12-10
18:57 [PhD][New]

Name: Miklos Santha

18:57 [PhD][Update]

Name: Henri Gilbert
Topic: Cryptanalyse des algorithmes de chiffrement symétrique
Category:secret-key cryptography

15:32 [Job][New]

The Laboratory of Algorithms, Cryptology and Security (LACS) at the University of Luxembourg is looking for one post-doc and one Ph.D. student to work on a new project on Fully Homomorphic Encryption (FHE). The goal is to improve existing FHE schemes, and possibly design and implement new ones.

The post-doc candidate should have a Ph.D. in cryptography. Experience with FHE is a plus but not a necessity. The Ph.D. candidate should have a master in computer science or in mathematics. Both positions are for three years.

Ph.D. student: http://recruitment.uni.lu/en/details.html?nPostingTargetID=5414

Post-doc: http://recruitment.uni.lu/en/details.html?nPostingTargetId=5426

15:32 [Job][New]

Starting 2015 the Information Security & Cryptography Group at Saarland

University, Germany, has several open positions for postdocs and we are

Our major current research focus is on the recently awarded ERC Synergy

Grant imPACT, which aims at providing foundations for privacy,

accountability, compliance and trust in the Internet of the Future,

including cutting-edge methods and tools for assessing and enhancing

customer privacy.

You have the chance to work at one of Europe\'s top sites for IT security

and privacy research, in the beautiful region between Germany, France

and Luxembourg with a high quality of life. Postdocs are paid employees

of Saarland University. Salary and employment conditions are attractive.

We encourage the application of outstanding PhDs in computer science or

IT security, who would like to work with us in the field of next

generation privacy techniques. The positions start from February 1, 2015

or later and are funded for two years, with a possible extension by one

year. We solicit applications by January 15, 2015, but we will consider

applications until the positions are filled. Applications should include a

curriculum vitae, a brief description of research interests, three

selected own publications, and, if available, letters of recommendation.

Applications and informal inquiries should be sent to Michael Backes at

the following email address: application-erc (at) mail-infsec.cs.uni-saarland.de

Further information:

Center for IT Security, Privacy and Accountability - http://cispa.saarland

Information Security & Cryptography Group -

http://www.infsec.cs.uni-saarland.de

ERC Synergy Grant imPACT - http://www.impact-erc.eu

04:17 [Pub][ePrint]

In the new age of cyberwars, system designers have

come to recognize the merits of building critical systems on top

of small kernels for their ability to provide strong isolation at

system level. This is due to the fact that enforceable isolation is

the prerequisite for any reasonable security policy. Towards this

goal we examine some internals of Fiasco.OC, a microkernel of

the prominent L4 family. Despite its recent success in certain highsecurity

projects for governmental use, we prove that Fiasco.OC

is not suited to ensure strict isolation between components meant

to be separated.

Unfortunately, in addition to the construction of system-wide

denial of service attacks, our identified weaknesses of Fiasco.OC

also allow covert channels across security perimeters with high

bandwidth. We verified our results in a strong affirmative way

through many practical experiments. Indeed, for all potential use

cases of Fiasco.OC we implemented a full-fledged system on its

respective archetypical hardware: Desktop server/workstation on

AMD64 x86 CPU, Tablet on Intel Atom CPU, Smartphone on

ARM Cortex A9 CPU. The measured peak channel capacities

ranging from 13500 bits/s (Cortex-A9 device) to 30500 bits/s

(desktop system) lay bare the feeble meaningfulness of Fiasco.

OC\'s isolation guarantee. This proves that Fiasco.OC cannot

be used as a separation kernel within high-security areas.

04:17 [Pub][ePrint]

We found a statistical weakness in the Spritz algorithm designed by Ronald L. Rivest and Jacob C. N. Schuldt. For N=8: Prob(output(x)=output(x+2)) = 1/N + 0.000498. The bias becomes statistically significant (for N=8) after observing about 2^21.9 outputs. Analogous bias occurs for N=16. We propose an algorithm (VMPC-R) which for N=8 produced 2^46.8 (31 million times more) outputs which remained undistinguishable from random in the same battery of tests. Supported by a series of additional statistical tests and security analyses we present VMPC-R as an algorithm we hope can be considered a worthwhile replacement for RC4.

04:17 [Pub][ePrint]

RECTANGLE is a newly proposed lightweight block cipher which allows fast implementations for multiple platforms by using bit-slice techniques. It is an iterative 25-round SPN block cipher with a 64-bit block size and a 80-bit or 128-bit key size. Until now, the results on analyzing the cipher are not too much, which includes an attack on the 18-round reduced version proposed by the designers themselves. In this paper, we find all 15-round differential characteristics with 26--30 active S-boxes for given input, output and round subkey differences, which have a total probability $2^{-60.5}$. Based on these differential characteristics, we extend the corresponding distinguisher to 2 rounds backward and forward respectively, and propose an attack on the 19-round reduced RECTANGLE-80 with data complexity of $2^{62}$ plaintexts, time complexity of about $2^{67.42}$ encryptions and memory complexity of $2^{72}$. TThese data and time complexities are much lower than that of the designers for the 18-round reduced RECTANGLE-80.

02:29 [PhD][New]

Name: Hassan Jameel Asghar
Topic: Design and Analysis of Human Identification Protocols
Category: cryptographic protocols

Description: Human identification protocols are authentication protocols that enable a human using an insecure terminal to authenticate to a remote server. The goal of such protocols is to ensure secure authentication in the presence of an adversary who can not only view the user’s inputs, and the internal computations and display of the terminal, but also eavesdrop on the communication link between the terminal and the server. An active\r\nadversary can in addition actively interfere with this communication link. However, protocols secure against active adversaries fall well short of usability. As a result, the focus of recent research has been on security against passive adversaries. Traditional authentication methods such as password-based authentication are not secure under this model, since the adversary can impersonate the user by learning the user’s password after observing a single authentication session.\r\n\r\nSince the introduction of the problem by Matsumoto and Imai in 1991, there have been sporadic attempts at constructing secure human identification protocols. However, to date there is no accepted solution, mainly because such protocols require mental computations from humans, and therefore the tradeoff between security and usability is huge. State-of-the-art protocols take between one to three minutes for authentication, but guarantee stronger security than traditional authentication methods. While this authentication time is not acceptable for most practical purposes, many interesting new mathematical problems and ideas have resulted in search for usable protocols.\r\n\r\nThis thesis aims to further the research in human identification protocols by focusing on the mathematical and analytical aspects of such protocols. We generalize some aspects of these protocols by analyzing their general structure. We give detailed security analysis of two protocols from literature, showing that without a thorough security analysis, these protocols are vulnerable to simple[...]

02:29 [PhD][New]

Name: Karine Heydemann

02:29 [PhD][Update]

Name: Nicolas Moro
Topic: Security of assembly programs against fault attacks on embedded processors
Category:implementation

Description: This thesis focuses on the security of embedded programs against fault injection attacks. Due to the spreadings of embedded systems in our common life, development of countermeasures is important. First, a fault model based on practical experiments with a pulsed electromagnetic fault injection technique has been built. The experimental results show that the injected faults were due to the corruption of the bus transfers between the Flash memory and the processor’s pipeline. Such faults enable to perform instruction replacements, instruction skips or to corrupt some data transfers from the Flash memory. Although replacing an instruction with another very specific one is very difficult to control, skipping an instruction seems much easier to perform in practice and has been observed very frequently. Furthermore many simple attacks can carried out with an instruction skip. A countermeasure that prevents such instruction skip attacks has been designed and formally verified with model-checking tool. The countermeasure replaces each instruction by a sequence of instructions. However, this countermeasure does not protect the data loads from the Flash memory. To do this, it can be combined with another assembly-level countermeasure that performs a fault detection. A first experimental test of these two countermeasures has been achieved, both on isolated instructions and complex codes from a FreeRTOS implementation. The proposed countermeasure appears to be a good complement for this detection countermeasure and allows to correct some of its flaws.[...]

2014-12-07
16:17 [Pub][ePrint]

In CRYPTO 2014 Albrecht \\emph{et al.} brought in a 20-round iterative lightweight block

cipher PRIDE which is based on a good linear layer for achieving a

tradeoff between security and efficiency. A recent

analysis is presented by Zhao \\emph{et al.}. Inspired by their work, we use an

automatic search method to find out 56 iterative differential characteristics of PRIDE, containing 24

1-round iterative characteristics, based on three of them we construct a 15-round differential and perform a differential attack on the 19-round PRIDE, with data,

time and memory

complexity of $2^{62}$, $2^{63}$ and $2^{71}$ respectively.