SADPonzi: Detecting and Characterizing Ponzi Schemes in Ethereum Smart Contracts

2021 ◽  
Vol 5 (2) ◽  
pp. 1-30
Author(s):  
Weimin Chen ◽  
Xinran Li ◽  
Yuting Sui ◽  
Ningyu He ◽  
Haoyu Wang ◽  
...  
Keyword(s):  
Machine Learning ◽  
Semantic Information ◽  
Symbolic Execution ◽  
Experimental Result ◽  
Smart Contracts ◽  
Smart Contract ◽  
Detection Approach ◽  
Ponzi Scheme ◽  
Feasible Path ◽  
Definition Of

Ponzi schemes are financial scams that lure users under the promise of high profits. With the prosperity of Bitcoin and blockchain technologies, there has been growing anecdotal evidence that this classic fraud has emerged in the blockchain ecosystem. Existing studies have proposed machine-learning based approaches for detecting Ponzi schemes, i.e., either based on the operation codes (opcodes) of the smart contract binaries or the transaction patterns of addresses. However, state-of-the-art approaches face several major limitations, including lacking interpretability and high false positive rates. Moreover, machine-learning based methods are susceptible to evasion techniques, and transaction-based techniques do not work on smart contracts that have a small number of transactions. These limitations render existing methods for detecting Ponzi schemes ineffective. In this paper, we propose SADPonzi, a semantic-aware detection approach for identifying Ponzi schemes in Ethereum smart contracts. Specifically, by strictly following the definition of Ponzi schemes, we propose a heuristic-guided symbolic execution technique to first generate the semantic information for each feasible path in smart contracts and then identify investor-related transfer behaviors and the distribution strategies adopted. Experimental result on a well-labelled benchmark suggests that SADPonzi can achieve 100% precision and recall, outperforming all existing machine-learning based techniques. We further apply SADPonzi to all 3.4 million smart contracts deployed by EOAs in Ethereum and identify 835 Ponzi scheme contracts, with over 17 million US Dollars invested by victims. Our observations confirm the urgency of identifying and mitigating Ponzi schemes in the blockchain ecosystem.

scholarly journals THE CONCEPT OF SMART CONTRACTS FROM THE LEGAL PERSPECTIVE

2019 ◽  
Vol 34 (3) ◽  
Author(s):  
Karolina Kasprzyk
Keyword(s):  
Contract Law ◽  
Regulatory Framework ◽  
Legal Issues ◽  
Comparative Perspective ◽  
Smart Contracts ◽  
Legal Definition ◽  
Smart Contract ◽  
Legal Perspective ◽  
Definition Of

The purpose of article hereof is to introduce the significant characters of the smart contracts and certain ideas and proposals de lege ferenda on regulatory framework for smart contracts. Furthermore, present legislation with regard to the legal definition of the smart contract will be discussed from a comparative perspective. Particular note will be devoted to smart contracts in a relation to the contract law. Substantively, legal issues arising from the use of smart contracts, focussing upon actual and potential conflicts with established principles of contract law, will be introduced.

scholarly journals Advantages and disadvantages of smart-contracts as the basis for the emergence of ownership

2021 ◽  
pp. 101-105
Author(s):  
K. Nekit
Keyword(s):  
Property Rights ◽  
Legal Aspect ◽  
Legal Regulation ◽  
Third Party ◽  
Smart Contracts ◽  
Advantages And Disadvantages ◽  
Technical Errors ◽  
Smart Contract ◽  
Legal Nature ◽  
Definition Of

The article examines the concepts, legal nature of smart contracts, as well as the advantages and disadvantages of smart contracts as a basis for ownership. The technical and legal aspect of the concept of smart contract is considered. Models of using smart contracts are described. Approaches to determining the legal nature of smart contracts are presented. It is concluded that two models must be considered when using smart contracts. The first model is external, when the program code does not replace the agreement, but only automates its execution. The second model is internal, when the code completely or partially replaces the terms of the agreement. Among the advantages of smart contracts as grounds for the emergence of property rights can be identified, first of all, the inability to change the terms of the contract and interference in its work. However, at the same time, this feature is a disadvantage of the smart contract, as it does not allow to take into account the objective circumstances that may affect the implementation of the agreement. The problem of oracles when using smart contracts is also considered. It is noted that the use of oracles actually means the involvement of a third party in the transaction with all the risks that arise from it. The problem of involving notaries and state registrars in transactions on acquisition of property rights on the basis of a smart contract is analyzed. The problems of lack of legal regulation of smart contracts, in particular, related to its transnational nature, is investigated. The problem of protection of the rights of the parties to the smart contract is analyzed, in particular, related to technical errors and outside interference. Temporary solutions regarding the use of smart contracts and general recommendations on the legislative definition of smart contracts are proposed.

The Legality of Smart Contracts in a Decentralized Autonomous Organization (DAO)

2022 ◽  
pp. 112-131
Author(s):  
Andasmara Rizky Pranata ◽  
Pardis Moslemzadeh Tehrani
Keyword(s):  
Smart Contracts ◽  
Smart Contract ◽  
Legal Contract ◽  
Five Elements ◽  
The Law ◽  
Definition Of

This chapter discuss the legality of smart contract in a decentralized autonomous organization (DAO). The regulation framework of blockchain is developing rapidly with many countries such as Malta and Estonia utilizing and allowing the use of blockchain. While many researchers have discussed the legality of smart contract, its relation to DAO as one of blockchain's applications is rarely discussed. There are three issues discussed in this chapter: the definition of DAO, the definition of smart contract, and the legality of smart contract in DAO. Each country has their own legal threshold of a contract's legality, but there are generally five elements in a legal contract, namely offer and acceptance, consideration, intention, certainty, and completeness. It is possible for the smart contract to fulfil the five legal elements of a contract. As there are different regulations in different countries, there may have been different elements to the law. In conclusion, the legality of smart contracts, like blockchain itself, depends on who uses it, where it is used, and how it is used.

scholarly journals Smart contract: from definition to certainty

2021 ◽  
Vol 1 (1) ◽  
pp. 100-122
Author(s):  
Yuriy Truntsevsky ◽  
Vyacheslav Sevalnev
Keyword(s):  
Social Relations ◽  
New Technologies ◽  
Theory And Practice ◽  
Information Support ◽  
Smart Contracts ◽  
Legal Definition ◽  
Advantages And Disadvantages ◽  
Smart Contract ◽  
Wide Range ◽  
Definition Of

The purpose of the present article is to gain an understanding of the opportunities and difficulties created by the introduction and development of the practice of network (smart) contracts. Our research methodology is based on a holistic set of principles and methods of scholarly analysis employed by modern legal science. It uses a dialectical method involving both general approaches (structural system method, formal logical method, analysis and synthesis of individual elements, individual features of concepts, abstraction, generalization, etc.) and particular methods (legal technical, systematic, comparative, historical, and grammatical methods, method of the unity of theory and practice, etc.). We analyze the views of lawyers and other specialists from Russia and abroad, legislative innovations in the field of digital technologies, the practice of blockchain-based smart contracts, and the main risks (whether legal, technological, operational, or criminogenic) of smart contracts for economic activities with a study of their causes. In the present-day situation, it is necessary to move from the legal definition of the smart contract and its legal and technological characteristics, advantages and disadvantages to the implementation of startups in a wide range of areas, especially business, public regulation, and social relations. Scholarly and information support for such processes will contribute to the development of industry, public administration and digital technology applications to improve the life of individual citizens and society as a whole. The introduction of smart contracts does not require the adoption of new laws or regulations. Instead, one should adapt and, possibly, modify existing legal principles at the legislative and judicial levels to pave the way for the use of smart contracts and other new technologies. The system of contract law provides a sufficient framework for regulating transactions without the introduction of any new legal categories. We propose approaches to the legal definition of the smart contract and identify a set of problems that must be solved at the legislative and technical legal levels in order to implement smart contracts effectively in different spheres of life.

scholarly journals A Novel Machine Learning-Based Analysis Model for Smart Contract Vulnerability

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Yingjie Xu ◽  
Gengran Hu ◽  
Lin You ◽  
Chengtang Cao
Keyword(s):  
Machine Learning ◽  
Denial Of Service ◽  
Structural Similarity ◽  
Data Sets ◽  
Smart Contracts ◽  
Abstract Syntax ◽  
Analysis Model ◽  
Abstract Syntax Tree ◽  
Syntax Tree ◽  
Smart Contract

In recent years, a lot of vulnerabilities of smart contracts have been found. Hackers used these vulnerabilities to attack the corresponding contracts developed in the blockchain system such as Ethereum, and it has caused lots of economic losses. Therefore, it is very important to find out the potential problems of the smart contracts and develop more secure smart contracts. As blockchain security events have raised more important issues, more and more smart contract security analysis methods have been developed. Most of these methods are based on traditional static analysis or dynamic analysis methods. There are only a few methods that use emerging technologies, such as machine learning. Some models that use machine learning to detect smart contract vulnerabilities cost much time in extracting features manually. In this paper, we introduce a novel machine learning-based analysis model by introducing the shared child nodes for smart contract vulnerabilities. We build the Abstract-Syntax-Tree (AST) for smart contracts with some vulnerabilities from two data sets including SmartBugs and SolidiFI-benchmark. Then, we build the Abstract-Syntax-Tree (AST) of the labeled smart contract for data sets named Smartbugs-wilds. Next, we get the shared child nodes from both of the ASTs to obtain the structural similarity, and then, we construct a feature vector composed of the values that measure structural similarity automatically to build our machine learning model. Finally, we get a KNN model that can predict eight types of vulnerabilities including Re-entrancy, Arithmetic, Access Control, Denial of Service, Unchecked Low Level Calls, Bad Randomness, Front Running, and Denial of Service. The accuracy, recall, and precision of our KNN model are all higher than 90%. In addition, compared with some other analysis tools including Oyente and SmartCheck, our model has higher accuracy. In addition, we spent less time for training .

SMART CONTRACT: CONCEPT, LEGAL REGULATION, ASPECTS OF CONSUMER PROTECTION

2021 ◽  
Vol 14 (4) ◽  
pp. 236-247
Author(s):  
IRINA VIKTOROVNA ERMAKOVA ◽  
◽  
◽  
Keyword(s):  
Social Relations ◽  
Legal Status ◽  
Legal Regulation ◽  
Fundamental Rights ◽  
Smart Contracts ◽  
Legal Norms ◽  
Legal Relationship ◽  
Smart Contract ◽  
The Subject ◽  
Definition Of

The subject of the research is legal norms aimed at regulating by law relations in the field of concluding and executing smart contracts, including issues of protecting the rights of the parties to such contracts, including consumers. The object of the research is social relations arising in the process of creating, concluding and executing of smart contracts. Particular attention is paid to the theoretical and practical aspects of the definition of the concept of “smart contract” and its essence, as well as its legal status. In addition, the article considers approaches to defining the essence of institutions that are closely related to the category of “smart contract”, such as “cryptocurrency”, “digital ruble”, “mining”. The aspects of the protection of fundamental rights of the parties involved in the considered legal relationship, including consumers, are also analyzed. Examples of court decisions regarding the corresponding category of cases are given. The novelty of the research lies in determining the current approaches in relation to the essence, concept and legal status of smart contracts, including the current position of law enforcement practice in relation to this issue. In addition, the novelty of the study lies in considering the practical aspects of the conclusion and execution of smart contracts, including, indicating examples of blockchain platforms on the basis of which smart contracts can function. Ultimately, the study led to the development by the author of some proposals in order to improve the relevant legislation. In particular, the author proposed to consolidate at the legislative level the legal definition of the concept of “smart contract”, indicating the appropriate wording.

scholarly journals Legal regulation of smart contracts in France

2019 ◽  
pp. 151-158
Author(s):  
D. V. Chub
Keyword(s):  
Legal Status ◽  
Legal Regulation ◽  
Smart Contracts ◽  
French Law ◽  
Legal Doctrine ◽  
Economic Relations ◽  
Smart Contract ◽  
Legal Obligations ◽  
Characteristic Features ◽  
Definition Of

The paper is devoted to the legal regulation of smart contracts in French law. The question of the admissibility of the use of smart contracts in economic relations is considered. Particular attention is given to the French legal doctrine in the issue of formulating the definition of “smart contract” and identifying its characteristic features, the various points of view of French legal scholars are compared. Examples of the most effective use of a smart contract in economic relations are given. The problems of applying contractual legal obligations and obligations of French law to smart contracts are considered. The importance of the oracle for the implementation of the smart contract and the features of its legal status under French law are disclosed.

scholarly journals Density Based Mode Within Radius and Its Application to EEG based Emotion Recognition

2021 ◽  
Vol 34 (1) ◽  
Author(s):  
Parampuneet Thind ◽  
Vaibhav Katturu ◽  
Teryn Cha ◽  
Sung-Hyuk Cha
Keyword(s):  
Machine Learning ◽  
Emotion Recognition ◽  
Statistical Parameter ◽  
Experimental Result ◽  
Statistical Parameters ◽  
Definition Of ◽  
Electroencephalogram Eeg

Statistical parameters such as center points are widely used to represent patterns in machine learning. There are three popular center points: mean, median, and mode. Mean and median are pervasively used as features to represent patterns, but mode is not because of its weakness. One of the major problems in the conventional definition of mode occurs when the distribution is multimodal with tied multiple maximum points. Hence, in this paper we propose a modified version of mode, which utilizes the density within a radius. The effectiveness of proposed mode is demonstrated in the emotion recognition application using the Electroencephalogram (EEG). An experimental result of amalgamating statistical parameters with a new modified parameter suggests the superiority of the proposed statistical parameter over the traditional measures.  

Research on Hyperpaths in the Urban Rail Transit Network

2014 ◽  
Vol 488-489 ◽  
pp. 1439-1443
Author(s):  
Jin Hai Li ◽  
Jian Feng Liu
Keyword(s):  
Large Scale ◽  
Urban Rail Transit ◽  
Rail Transit ◽  
Transit Network ◽  
Travel Costs ◽  
Urban Rail ◽  
Distinctive Structure ◽  
Feasible Path ◽  
Definition Of ◽  
Urban Rail Transit Network

Hyperpaths enumeration is one of the basic procedures in many traffic planning issues. As a result of its distinctive structure, hyperpaths in Urban Rail Transit Network (URTN) are different from those in road network. Typically, one may never visit a station more than once and would never transfer from one line to another that has been visited in a loopless URTN, meaning that stations a hyperpath traversed cannot be repeated, neither do lines in loopless networks. This paper studies the relationships between feasible path and the shortest path in terms of travel costs. In this paper, a new definition of hyperpath in URTN is proposed and a new algorithm based on the breadth first searching (BFS) method is presented to enumerate the hyperpaths. The algorithm can safely avoid hyperpath omission and can even be applied in networks containing loops as well. The influence of parameters on hyperpaths is studied by experimentally finding hyperpaths in the subway network in Beijing. A group of suggested parameter pairs are then given. Finally, a numerical experiment is used to illustrate the validity of the proposed algorithm. The results imply the significance of the convergence of the BFS algorithm which can be used to search hyperpaths in large scale URTN even with loop.

Machine learning steered symbolic execution framework for complex software code

2021 ◽  
Author(s):  
Lei Bu ◽  
Yongjuan Liang ◽  
Zhunyi Xie ◽  
Hong Qian ◽  
Yi-Qi Hu ◽  
...  
Keyword(s):  
Machine Learning ◽  
Symbolic Execution ◽  
Software Code
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