Attack Algorithm Research Articles

On the anonymizability of graphs

Many applications such as social networks, recommendation systems, email communication patterns, and other collaborative applications are built on top of graph infrastructures. The data stored on such networks may contain personal information about individuals and may therefore be sensitive from a privacy point of view. Therefore, a natural solution is to remove identifying information from the nodes and perturb the graph structure, so that re-identification becomes difficult. Typical graphs encountered in real applications are sparse. In this paper, we will show that sparse graphs have certain theoretical properties which make them susceptible to re-identification attacks. We design a systematic way to exploit these theoretical properties in order to construct re-identification signatures, which are also known as characteristic vectors. These signatures have the property that they are extremely robust to perturbations, especially for sparse graphs. We use these signatures in order to create an effective attack algorithm. We supplement our theoretical results with experimental tests using a number of algorithms on real data sets. These results confirm that even low levels of anonymization require perturbation levels which are significant enough to result in a massive loss of utility. Our experimental results also show that the true anonymization level of graphs is much lower than is implied by measures such as $$k$$k-anonymity. Thus, the results of this paper establish that the problem of graph anonymization has fundamental theoretical barriers which prevent a fully effective solution.

The Alberta Stroke Prevention in TIAs and Mild Strokes (ASPIRE) Intervention: Rationale and Design for Evaluating the Implementation of a Province-Wide TIA Triaging System

Stroke risk after transient ischaemic attack is high and, it is a challenge worldwide to provide urgent assessment and preventive services to entire populations. To determine whether a province-wide transient ischaemic attack Triaging algorithm and transient ischaemic attack hotline (the Alberta Stroke Prevention in transient ischaemic attacks and mild strokes intervention) can reduce the rate of stroke recurrence following transient ischaemic attack across the population of Alberta, Canada (population 3·7 million, 90-day rate of post-stroke transient ischaemic attack currently 9·5%). It also seeks to improve upon current transient ischaemic attack triaging rules by incorporating time from symptom onset as a predictive variable. The transient ischaemic attack algorithm and hotline were developed with a broad consensus of clinicians, patients, policy-makers, and researchers and based on local adaptation of the work of others and research and insights developed within the province. Because neither patient-level nor region-level randomization was possible, we conducted a quasi-experimental design examining changes in the post-transient ischaemic attack rate of stroke recurrence before and after the 15-month implementation period using an interrupted time-series regression analysis. The design controls for changes in case-mix, co-interventions, and secular trends. A prospective transient ischaemic attack cohort will also be concurrently created with telephone follow-up at seven-days and 90 days as well as passive follow-up over the longer term using linkages to provincial healthcare administrative databases. The primary outcome measure is the change in recurrence rate of stroke following transient ischaemic attack at seven-days and 90 days, comparing a period of two-years before vs. two-years after the intervention is implemented. All cases of recurrent stroke will be validated. Secondary outcomes include functional status, hospitalizations, morbidity, and mortality. We are undertaking a rigorous evaluation of a population-based approach to improving quality of transient ischaemic attack care. Whether positive or negative, our work should provide important insights for all potential stakeholders.

Masquerade attack on transform-based binary-template protection based on perceptron learning

With the increasing deployment of biometric systems, security of the biometric systems has become an essential issue to which serious attention has to be given. To prevent unauthorized access to a biometric system, protection has to be provided to the enrolled biometric templates so that if the database is compromised, the stored information will not enable any adversary to impersonate the victim in gaining an illegal access. In the past decade, transform-based template protection that stores binary one-way-transformed templates (e.g. Biohash) has appeared being one of the benchmark template protection techniques. While the security of such approach lies in the non-invertibility of the transform (e.g. given a transformed binary template, deriving the corresponding face image is infeasible), we will prove in this paper that, irrespective of whether the algorithm of transform-based approach is revealed, a synthetic face image can be constructed from the binary template and the stolen token (storing projection and discretization parameters) to obtain a highly-probable positive authentication response. Our proposed masquerade attack algorithms are mainly composed of a combination of perceptron learning and customized hill climbing algorithms. Experimental results show that our attack algorithms achieve very promising results where the best setting of our attack achieves 100% and 98.3% rank one recognition rates for the CMU PIE and FRGC databases correspondingly when the binarization algorithm (transformation plus discretization) is known; and 85.29% and 46.57% rank one recognition rates for the CMU PIE and FRGC databases correspondingly when the binarization algorithm is unknown.

Double random phase encoding using phase reservation and compression

In recent years, various studies have been conducted to illustrate the vulnerability of double random phase encoding (DRPE). In this paper, we propose a novel method via phase reservation and compression to enhance DRPE security. Only a compressed phase distribution is available in the CCD plane, and the amplitude component is not available or requested for optical decryption. Since only noise-like distributions can be obtained by using the correct security keys during optical decryption, a nonlinear correlation algorithm is further applied for authenticating the decrypted image. It is demonstrated that valid conditions for attack algorithms are broken and high security can be achieved for the DRPE system.

Traceability Attack Algorithm on EOHLCAP RFID Authentication Protocol

W e analyze a recent RFID lightweight authentication protocol, namely EOHLCAP scheme . Based on our analysis, however, a new traceability attack algorithm makes the scheme insecurity, if the attacker has the ability to distinguish the target tag . So me lightweight authentication protocol s are susceptible to the similar traceability attack, so we propose a new traceability attack algorithm. More precisely, we also show how our attack algorithm can be applied to the older schemes. To counteract such security issue, we revise the EOHLCAP scheme with the rotation operation and show that the proposed model satisfies the indistinguishability property. Finally, we introduce a revised protocol, name ly EOHLCA P+ scheme, which conforms to the security requirement and resists the tracing attack.

Enhancing Efficiency of Node Compromise Attacks in Vehicular Ad-hoc Networks Using Connected Dominating Set

In the node compromise attack, the adversary physically captures nodes and extracts the cryptographic keys from the memories, which destroys the security, reliability and confidentiality of the networks. Due to the dynamical network topology, designing an efficient node compromise attack algorithm is challenging, because it is difficult to model the attack or to enhance the attacking efficiency. In this paper, a general algorithm for modeling the node compromise attack in VANET is proposed, which promotes the attacking efficiency by destroying the network backbone. The backbone is constructed using the connected dominating set of the network, which has relevant to the intermeeting time between the vehicles. Then two attacking algorithms are proposed based on the general model, which destroy the network in a centralized and distributed version while maximizing the destructiveness. Simulations are conducted to show the advantages of our scheme. Simulation results reveal that our scheme enhances the attacking efficiency in different mobility models and different applications, which is suitable for modeling the node compromise attack in VANET. At last, discussions are presented to the illustrate the influences of the characteristics to the attacking efficiency with respect to vehicle speed, communication range and key sharing probability.

On Identity Disclosure Control for Hypergraph-Based Data Publishing

Data publishing based on hypergraphs is becoming increasingly popular due to its power in representing multirelations among objects. However, security issues have been little studied on this subject, while most recent work only focuses on the protection of relational data or graphs. As a major privacy breach, identity disclosure reveals the identification of entities with certain background knowledge known by an adversary. In this paper, we first introduce a novel background knowledge attack model based on the property of hyperedge ranks, and formalize the rank-based hypergraph anonymization problem. We then propose a complete solution in a two-step framework: rank anonymization and hypergraph reconstruction. We also take hypergraph clustering (known as community detection) as data utility into consideration, and discuss two metrics to quantify information loss incurred in the perturbation. Our approaches are effective in terms of efficacy, privacy, and utility. The algorithms run in near-quadratic time on hypergraph size, and protect data from rank attacks with almost the same utility preserved. The performances of the methods have been validated by extensive experiments on real-world datasets as well. Our rank-based attack model and algorithms for rank anonymization and hypergraph reconstruction are, to our best knowledge, the first systematic study to privacy preserving for hypergraph-based data publishing.

Enhancing the attacking efficiency of the node capture attack in WSN: a matrix approach

In the node capture attack, the adversary intelligently captures nodes and extracts the cryptographic keys from their memories to destroy the security, reliability and confidentiality of the wireless sensor networks. However, it suffers from low attacking efficiency and high resource expenditure. In this paper, we approach this attack from an adversarial view and develop a matrix-based method to model the process of the node capture attack. We establish a matrix to indicate the compromising relationship between the nodes and the paths. We propose a Matrix-based node capture attack Algorithm (MA in short), which can maximize the destructiveness while consuming the minimum resource expenditure. We conduct several experiments to show the performance of MA. Experimental results manifest that MA can reduce the attacking round, shorten the execution time, enhance the attacking efficiency and conserve the energy cost.

Lexical active attack on chaotic text zero-watermarking

The conventional steganalysis techniques does not work in zero-watermarking technology because it does not modify carrier text.However,active attack model on text zero-watermarking has not been well studied.In order to solve this problem,an active attack algorithm for text zero-watermarking was proposed.Making use of synonym substitution technology,sync-attack and birthday-attack were defined.Through combining the two active attack methods,a lexical active attack algorithm on text zero-watermarking was designed and implemented.The experimental result shows the proposed algorithm can effectively destroy zero-watermarking without modifying carrier text massively.

On the Security of Pseudorandomized Information-Theoretically Secure Schemes

In this paper, we discuss a naive method of randomness reduction for cryptographic schemes, which replaces the required perfect randomness with output distribution of a computationally secure pseudorandom generator (PRG). We propose novel ideas and techniques for evaluating the indistinguishability between the random and pseudorandom cases, even against an adversary with computationally unbounded attack algorithm. Hence, the PRG-based randomness reduction can be effective even for information-theoretically secure cryptographic schemes, especially when the amount of information received by the adversary is small. In comparison to a preceding result of Dubrov and Ishai (STOC 2006), our result removes the requirement of generalized notion of “nb-PRGs” and is effective for more general kinds of protocols. We give some numerical examples to show the effectiveness of our result in practical situations, and we also propose a further idea for improving the effect of the PRG-based randomness reduction.

The Improved 96th-Order Differential Attack on 11 Rounds of the Block Cipher CLEFIA

CLEFIA is a 128-bit block cipher proposed by Shirai of SONY et al. in 2007. Its key size is 128, 192, or 256 bits. The number of the round of data processing part depends on a key size, viz. it is 18, 22, or 26 rounds for 128, 192, or 256 bits of a key size, respectively. Such a characteristic of CLEFIA have been known that the 96th- order differential of 64 bits out of 128 bits of the 8th-round's output is zero. With this characteristic, we reported the 96th-order differential attack on 11 rounds of CLEFIA that requires 2 98.3 blocks of plain text and 2 159 times of data encryption. In this paper, we reduce this number of the times of the encryption, (viz. computational complexity) by applying a partial sum technique proposed by Ferguson et al. With the technique, we sequentially derive a modulo 2 occurrence distribution of intermediate data of cryptanalysis. We also reduce the complexity by introducing a nested structure of iterative computations to the attack algorithm. As a result we reduce the complexity to 2 106.6 , which is 1/2 52.4 of the conventional complexity. 

Nonadaptive Mastermind Algorithms for String and Vector Databases, with Case Studies

In this paper, we study sparsity-exploiting Mastermind algorithms for attacking the privacy of an entire database of character strings or vectors, such as DNA strings, movie ratings, or social network friendship data. Based on reductions to nonadaptive group testing, our methods are able to take advantage of minimal amounts of privacy leakage, such as contained in a single bit that indicates if two people in a medical database have any common genetic mutations, or if two people have any common friends in an online social network. We analyze our Mastermind attack algorithms using theoretical characterizations that provide sublinear bounds on the number of queries needed to clone the database, as well as experimental tests on genomic information, collaborative filtering data, and online social networks. By taking advantage of the generally sparse nature of these real-world databases and modulating a parameter that controls query sparsity, we demonstrate that relatively few nonadaptive queries are needed to recover a large majority of each database.

Cryptographic Properties and Quadratic Equations of S-Box in SMS4

Analysis of the S-box password SMS4 algorithm characteristics, discussed the algorithm of S-box algebraic balance, nonlinearity, avalanche characteristics, diffusion characteristics, and XLS attack the related quadratic equation number. Compared with the S-box of AES, Camellia algorithm, algorithm SMS4 S-box design has reached the standards of Europe and the United States block cipher standard algorithm for the S-box design. However, the algorithm's overall security features remains to be further studied.

A high efficient node capture attack algorithm in wireless sensor network based on route minimum key set

ABSTRACTWireless sensor networks are often deployed in hostile and unattended environment that are very prone to node capture attack. In node capture attack, information such as key, data on captured nodes, can all be extracted by the adversary. Node capture attack in wireless sensor networks suffers from low efficiency and high resource expenditure. To enhance the efficiency of node capture attack, we propose here a high efficiency node capture attack algorithm that is based on route minimum key set, namely greedy node captured based on route minimum key set (GNRMK). To obtain the route minimum key set, the sensor network is mapped as a flow network. The route minimum key set can be calculated by the maximum flow of the flow network. Then, an overlapping value is assigned to each node on the basis of route minimum key set. The node with maximum overlapping value will be captured in every round of attack. Simulation results indicate that, compared with other node capture attack schemes, GNRMK can compromise the network by capturing fewer nodes. Moreover, the fraction of traffic compromised is much higher. Copyright © 2012 John Wiley & Sons, Ltd.

A hybrid strategy for cryptanalysis of optical encryption based on double-random phase–amplitude encoding

A hybrid two-step attack scheme that combines the chosen-plaintext attack (CPA) and the known-plaintext attack (KPA) algorithms is proposed to acquire the secret keys of the optical cryptosystem based on double-random phase–amplitude encoding (DRPAE) technique. By implementing our presented attack, an opponent can obtain not only the estimated solutions of the two random phase keys but also the accurate solution of the amplitude modulator (AM), which is introduced to the encryption process and regarded as an additional key to enhance the security level of the DRPAE-based cryptosystem. The validity and effectiveness of this attack strategy is analyzed theoretically and then verified by computer simulations.

Path Planning of UAV Based on Voronoi Diagram and DPSO

This paper presents a solution strategy for achieving cooperative timing among teams of vehicles. The initial paths are constructed based on Voronoi diagram and based on that, the smoothing paths are designed for the Waypoint Path Planner (WPP). Then it considers the cooperative timing problem and proposes a particle swam optimization algorithm for simultaneous attack. Simulation results show that the approach is of high efficiency in multi-UAVs cooperative timing problem.

An Efficient and Provably-secure Digital signature Scheme based on Elliptic Curve Bilinear Pairings

We proposed an efficient and secure digital signature scheme using elliptic curve cryptography (ECC) and bilinear pairings in this paper. The proposed scheme employs the general cryptographic hash function (i.e., SHA-1) instead of map-to-point function, because the map-to-point is a cost-intensive operation and it is usually implemented as a probabilistic algorithm. Further, our scheme is computationally efficient as one bilinear paring and three elliptic curve scalar point multiplication operations are executed for signature generation and verification, and thus the scheme requires much lesser computation cost than other related schemes. In addition, in the random oracle model, our scheme is proven to be existential unforgeable against the adaptive chosen message and identity attacks (EUF-CMA) based on a variation of the collusion attack algorithm with ktraitors (k-CAA3) problem.

On the Hardness of Subset Sum Problem from Different Intervals

SUMMARY The subset sum problem, which is often called as the knapsack problem, is known as an NP-hard problem, and there are several cryptosystems based on the problem. Assuming an oracle for shortest vector problem of lattice, the low-density attack algorithm by Lagarias and Odlyzko and its variants solve the subset sum problem efficiently, when the “density” of the given problem is smaller than some threshold. When we define the density in the context of knapsack-type cryptosystems, weights are usually assumed to be chosen uniformly at random from the same interval. In this paper, we focus on general subset sum problems, where this assumption may not hold. We assume that weights are chosen from different intervals, and make analysis of the effect on the success probability of above algorithms both theoretically and experimentally. Possible application of our result in the context of knapsack cryptosystems is the security analysis when we reduce the data size of public keys.

Repair Method of Complex Network Based on Matthew Effect

Complex network repair after suffering the deliberate assault becomes extraordinarily important. In this paper, a repair method of complex network based on Matthew Effect was proposed. Single-node selective attack algorithm and multi-node cluster attack algorithm was given. Aiming at the two kinds of attack, linear detection algorithm and BA network generation algorithm was put forward to get experiment data. Correspondingly, repair experiments were done. Experimental results show that repair rate of the method is more than 95% in sampling Internet and BA network. For repair rate of complex network, the conception of stability and its mathematics description was addressed. Experiments show that the complex network can achieve a steady topology state after some steps of attacks and repairs.

Correlation power analysis of DECIM v2

Power analysis has been a powerful and thoroughly studied threat for implementations of block ciphers and public key algorithms but not yet for stream ciphers. Based on the consumed power differences between two neighboring clock cycles, this paper presents a correlation power analysis (CPA) attack on the synchronous stream cipher DECIM v2 (the tweaked version of the original submission DECIM). This attack resynchronizes the cryptographic device ceaselessly with many different initialization values (IVs) to obtain enough power traces. Then by modeling the statistical properties of the differential power traces with the correlation coefficients, the proposed attack algorithm can completely reveal the secret key of DECIM v2. Furthermore, a simulation attack is mounted to confirm the validity of the algorithm. The results show that the entire secret key of DECIM v2 can be restored within several minutes by performing 12 CPA attacks. It seems that there are still some defects in the design of DECIM v2 and thus some further improvements should be made to resist the proposed attack.