Generic Attacks Research Articles

Critique of the related-key attack concept

In a related-key attack, an attacker seeks to discover the secret key by requesting encryptions under keys related to the secret key in a manner chosen by the attacker. We describe a new related-key attack against generic ciphers, requiring just O(1) work to distinguish a cipher from random, and O(key length) to completely recover the secret key. This attack applies within a model which was not previously known to be vulnerable, undermining the theoretical foundation of the related-key attack concept. We propose a new definition of related-key security, which prevents all known generic attacks including this new attack. We discuss the theoretical consequences of this new definition.

Scalability and Security Conflict for RFID Authentication Protocols

RFID technology continues to flourish as an inherent part of virtually every ubiquitous environment. However, it became clear that the public--implying the industry--seriously needs mechanisms emerging the security and privacy issues for increasing RFID applications. As the nodes of RFID systems mostly suffer from low computational power and small memory size, various attempts which propose to implement the existing security primitives and protocols, have ignored the realm of the cost limitations and failed. In this study, two recently proposed protocols--SSM and LRMAP--claiming to meet the standard privacy and security requirements are analyzed. The design of both protocols based on defining states where the server authenticates the tag in constant time in a more frequent normal state and needs a linear search in a rare abnormal states. Although both protocols claim to provide untraceability criteria in their design objectives, we outline a generic attack that both protocols failed to fulfill this claim. Moreover, we showed that the SSM protocol is vulnerable to a desynchronization attack which prevents a server from authenticating a legitimate tag. Resultantly, we conclude that defining computationally unbalanced tag states yields to a security/scalability conflict for RFID authentication protocols.

TWISTERπ – a framework for secure and fast hash functions

In this paper we present TWISTER π, a framework for hash functions. It is an improved version of TWISTER, a candidate of the NIST SHA-3 hash function competition. TWISTER π is built upon the ideas of wide pipe and sponge functions. The core of this framework is a – very easy to analyse – Twister-Round providing both extremely fast diffusion as well as collision-freeness for one internal Twister-Round. The total security level is claimed to be not below 2 n/2 for collision attacks and 2 n for (2nd) pre-image attacks. TWISTER π instantiations are secure against all known generic attacks. We also propose two instances TWISTER π-n for hash output sizes n = 256 and n = 512. These instantiations are highly optimised for 64-bit architectures and run very fast in hardware and software, e.g TWISTER π-256 is faster than SHA2-256 on 64-bit platforms and TWISTER π-512 is faster than SHA2-512 on 32-bit platforms. Furthermore, TWISTER π scales very well on low-end platforms.

Security Analysis of Two Augmented Password-Authenticated Key Exchange Protocols

An augmented PAKE (Password-Authenticated Key Exchange) protocol is said to be secure against server-compromise impersonation attacks if an attacker who obtained password verification data from a server cannot impersonate a client without performing off-line dictionary attacks on the password verification data. There are two augmented PAKE protocols where the first one [12] was proposed in the IEEE Communications Letters and the second one [15] was submitted to the IEEE P1363.2 standard working group [9]. In this paper, we show that these two augmented PAKE protocols [12], [15] (claimed to be secure) are actually insecure against server-compromise impersonation attacks. More specifically, we present generic server-compromise impersonation attacks on these augmented PAKE protocols [12], [15].

On the Need for Signal-Coherent Watermarks

Digital watermarking has been introduced in the 1990s as a complementary technology for copyright protection. In an effort to anticipate hostile behavior of adversaries, the research community is constantly introducing new attacks to benchmark watermarking systems. In this paper, we present a generic attack strategy based on block replacement. As multimedia content is often highly repetitive, the attack exploits signal's self-similarities to replace each signal block with another, perceptually similar one. Guided by the principles of the proposed attack framework, we implemented three attack algorithms for different types of multimedia content: video shots, audio tracks and still images. Finally, considering the effectiveness of the proposed algorithms, we identify the properties that a watermark should have to counter this attacking strategy

Watermarking via optimization algorithms for quantizing randomized semi-global image statistics

We introduce a novel approach for blind and semi-blind watermarking and apply it to images. We derive randomized robust semi-global statistics of images in a suitable transform domain (wavelets in case of images) and quantize them in order to embed the watermark. Quantization is effectively carried out by embedding to the host a computed sequence, which is obtained by solving an optimization problem whose parameters are known to the information hider but unknown to the attacker. An essential emphasis of the proposed method is randomization, which is crucial for security and robustness against arbitrary quality-preserving attacks. We formally show that malicious optimal estimation attacks that are specifically derived for our algorithm are ineffective in practice. Furthermore, we experimentally demonstrate that our watermarking method survives many generic benchmark attacks for a large number of images.

Worm Propagation and Generic Attacks

The defining task of propagating malicious code is to locate new targets to attack. Viruses search for files in a computer system to which to attach, whereas worms search for new targets to which to transmit themselves. Depending on their method of transmission, malicious code writers have developed different strategies for finding new victims. Worms transmitted via email have had great success propagating themselves because they find their next targets either by raiding a user's email address book or by searching through the user's mailbox. Such addresses are almost certain to be valid, permitting the worm to hijack the user's social web and exploit trust relationships. In most cases, the worm will craft its own message to send to the target, but some will wait for the user to send a message and attach themselves to it. Network worms, those that attack network services, must determine their next victim's IP address.

Hardware-Assisted Circumvention of Self-Hashing Software Tamper Resistance

Self-hashing has been proposed as a technique for verifying software integrity. Appealing aspects of this approach to software tamper resistance include the promise of being able to verify the integrity of software independent of the external support environment, as well as the ability to integrate code protection mechanisms automatically. In this paper, we show that the rich functionality of most modern general-purpose processors (including UltraSparc, x86, PowerPC, AMD64, Alpha, and ARM) facilitate an automated, generic attack which defeats such self-hashing. We present a general description of the attack strategy and multiple attack implementations that exploit different processor features. Each of these implementations is generic in that it can defeat self-hashing employed by any user-space program on a single platform. Together, these implementations defeat self-hashing on most modern general-purpose processors. The generality and efficiency of our attack suggests that self-hashing is not a viable strategy for high-security tamper resistance on modern computer systems.

The need for a new go-to-market strategy in Europe: How to survive and thrive in the new more complex healthcare marketplace

is a research analyst at Peppers & Rogers Group, Europe. Since joining the firm, Rodrigo has specialised in the Life Sciences Industry and has conducted extensive research on the value and relevance of CRM in the Life Sciences sector. Rodrigo holds a Bachelor's degree in Marketing and Psychology and a Master's degree in Marketing Management from Cranfield University. Keywords customer relationship management, European Pharmaceuticals, go-to-market model, key influencers, prescription drugs Abstract The European branded pharmaceutical industry is experiencing the most challenging business environment in years. As in other pharma markets in the world, the marketplace is increasingly difficult for the leading players. Generic attacks, parallel imports, meagre pipelines and patent challenges all affect the traditional business model. This paper focuses on the European pharmaceutical market in particular and explores the most recent changes within the regulatory environment that affect pharmaceutical companies. The paper depicts the increasing complexity of the network of influencers and concludes by looking at how pharmaceuticals companies can adapt to the changing conditions through the application of customer-centric interaction strategies. Sales and marketing will no longer be focused on a relatively small (and sceptical) group of customers, but will have to learn how to interact with other stakeholders such as payers, patients, nurses and pharmacists.

The Full Cost of Cryptanalytic Attacks

An open question about the asymptotic cost of connecting many processors to a large memory using three dimensions for wiring is answered, and this result is used to find the full cost of several cryptanalytic attacks. In many cases this full cost is higher than the accepted complexity of a given algorithm based on the number of processor steps. The full costs of several cryptanalytic attacks are determined, including Shanks’ method for computing discrete logarithms in cyclic groups of prime order n, which requires n 1/2+o(1) processor steps, but, when all factors are taken into account, has full cost n 2/3+o(1). Other attacks analyzed are factoring with the number field sieve, generic attacks on block ciphers, attacks on double and triple encryption, and finding hash collisions. In many cases parallel collision search gives a significant asymptotic advantage over well-known generic attacks.

Authentication protocols for mobile network environment value-added services

The secure provision of mobile computing and telecommunication services is rapidly increasing in importance as both demand and applications for such services continue to grow. This paper is concerned with the design of public key based protocols suitable for application in upcoming third-generation mobile systems such as the Universal Mobile Telecommunications Service. Candidate protocols are considered for the authentication of a mobile user to a value-added service provider with initialization of a mechanism enabling payment for the value-added service. A set of goals for such a protocol are identified, as are a number of generic attacks; these goals and attacks are then used to evaluate the suitability of seven candidate third-generation user-to-network authentication protocols. Many of these candidate protocols are shown to have highly undesirable features.

The Black-Box Model for Cryptographic Primitives

We introduce the black-box model for cryptographic primitives. In this model cryptographic primitives are given by a computation graph, where the computation boxes sitting on the vertices of the graph act as random oracles. We formalize and study a family of generic attacks which generalize exhaustive search and the birthday paradox. We establish complexity lower bounds for these attacks and we apply it to compression functions based on the FFT network.

Finite-difference time-domain analysis of HF antennas on helicopter airframes

In this paper, the finite-difference time-domain (FDTD) method with the Berenger perfectly matched layer (PML) absorbing boundary condition (ABC) is used to model the radiation characteristics of high frequency (HF) antennas operating in the 2-30 MHz range on a full-scale helicopter. The computed input impedance of both antennas is compared with actual measurements from an operational full-scale helicopter and also with measurements on a scale model NASA generic advanced attack helicopter (GAAH). To study the coupling effects of the helicopter fuselage on the antenna systems, the S-parameters are computed and compared with measurements on the NASA GAAH scale model. Finally, computed gain patterns are compared with actual in-flight measurements of the antenna systems on an operational full-scale helicopter.

Magnetohydrodynamic Submarine Propulsion Systems

ABSTRACTMagnetohydrodynamic propulsion systems for submarines offer several significant advantages over conventional propeller propulsion systems. These advantages include the potential for greater stealth characteristics, increased maneuverability, enhanced survivability, elimination of cavitation limits, greater payload capability, and the addition of a significant emergency propulsion system. These advantages can be obtained with a magnetohydrodynamic propulsion system that is neutrally buoyant and can operate with the existing submarine propulsion system power plant.A thorough investigation of magnetohydrodynamic propulsion systems for submarine applications has been completed. During the investigation, a number of geometric configurations were examined. Each of these configurations and mounting concepts was optimized for maximum performance for a generic attack class submarine. The optimization considered each thruster individually by determining the optimum operating characteristics for each one and accepting only those thrusters that result in a neutrally buoyant propulsion system.The results of this detailed optimization study show that the segmented, annular thruster is the concept with the highest performance levels and greatest efficiency and offers the greatest potential for a practical magnetohydrodynamic propulsion system for attack class submarines. The optimization study results were used to develop a specific point design for a segmented, annular magnetohydrodynamic thruster for an attack class submarine. The design point case has shown that this thruster may be able to provide the necessary thrust to propel an attack class submarine at the required velocity with the potential for a substantial acoustic signature reduction within the constraints of the existing submarine power plant and the maintenance of neutral buoyancy. This innovative magnetohydrodynamic propulsion system offers an approach for submarine propulsion that can be an important contribution to the development of the submarine force of the next century.