A systematic literature review of blockchain-based applications: Current status, classification and open issues

On blockchain and its integration with IoT. Challenges and opportunities

A survey on the security of blockchain systems

Permissionless blockchains allow the execution of arbitrary programs (called smart contracts), enabling mutually untrusted entities to interact without relying on trusted third parties. Despite their potential, repeated security concerns have shaken the trust in handling billions of USD by smart contracts. To address this problem, we present Securify, a security analyzer for Ethereum smart contracts that is scalable, fully automated, and able to prove contract behaviors as safe/unsafe with respect to a given property. Securify's analysis consists of two steps. First, it symbolically analyzes the contract's dependency graph to extract precise semantic information from the code. Then, it checks compliance and violation patterns that capture sufficient conditions for proving if a property holds or not. To enable extensibility, all patterns are specified in a designated domain-specific language. Securify is publicly released, it has analyzed >18K contracts submitted by its users, and is regularly used to conduct security audits by experts. We present an extensive evaluation of Securify over real-world Ethereum smart contracts and demonstrate that it can effectively prove the correctness of smart contracts and discover critical violations.

/pdf/securify-practical-security-analysis-of-smart-contracts-3m9isitgew.pdf

Securify: Practical Security Analysis of Smart Contracts

https://repository.tudelft.nl/islandora/object/uuid%3A17c5e959-3f00-404c-b4db-748968bdcc2c/datastream/OBJ/download

Blockchain in government: Benefits and implications of distributed ledger technology for information sharing

Smart contracts are computer programs that can be correctly executed by a network of mutually distrusting nodes, without the need of an external trusted authority. Since smart contracts handle and transfer assets of considerable value, besides their correct execution it is also crucial that their implementation is secure against attacks which aim at stealing or tampering the assets. We study this problem in Ethereum, the most well-known and used framework for smart contracts so far. We analyse the security vulnerabilities of Ethereum smart contracts, providing a taxonomy of common programming pitfalls which may lead to vulnerabilities. We show a series of attacks which exploit these vulnerabilities, allowing an adversary to steal money or cause other damage.

A Survey of Attacks on Ethereum Smart Contracts SoK

/pdf/a-survey-of-attacks-on-ethereum-smart-contracts-43l3b2jez9.pdf

A survey of attacks on Ethereum smart contracts.

Dissecting Ponzi schemes on Ethereum: Identification, analysis, and impact

Ponzi schemes are financial frauds which lure users under the promise of high profits. Actually, users are repaid only with the investments of new users joining the scheme: consequently, a Ponzi scheme implodes soon after users stop joining it. Originated in the offline world 150 years ago, Ponzi schemes have since then migrated to the digital world, approaching first the Web, and more recently hanging over cryptocurrencies like Bitcoin. Smart contract platforms like Ethereum have provided a new opportunity for scammers, who have now the possibility of creating "trustworthy" frauds that still make users lose money, but at least are guaranteed to execute "correctly". We present a comprehensive survey of Ponzi schemes on Ethereum, analysing their behaviour and their impact from various viewpoints.

Dissecting Ponzi schemes on Ethereum: identification, analysis, and impact

Albeit the primary usage of Bitcoin is to exchange currency, its blockchain and consensus mechanism can also be exploited to securely execute some forms of smart contracts. These are agreements among mutually distrusting parties, which can be automatically enforced without resorting to a trusted intermediary. Over the last few years a variety of smart contracts for Bitcoin have been proposed, both by the academic community and by that of developers. However, the heterogeneity in their treatment, the informal (often incomplete or imprecise) descriptions, and the use of poorly documented Bitcoin features, pose obstacles to the research. In this paper we present a comprehensive survey of smart contracts on Bitcoin, in a uniform framework. Our treatment is based on a new formal specification language for smart contracts, which also helps us to highlight some subtleties in existing informal descriptions, making a step towards automatic verification. We discuss some obstacles to the diffusion of smart contracts on Bitcoin, and we identify the most promising open research challenges.

/pdf/sok-unraveling-bitcoin-smart-contracts-xfpnjp0acd.pdf

Tiziana Cimoli

Papers

A Survey of Attacks on Ethereum Smart Contracts SoK

A survey of attacks on Ethereum smart contracts.

Dissecting Ponzi schemes on Ethereum: Identification, analysis, and impact

Dissecting Ponzi schemes on Ethereum: identification, analysis, and impact

SoK: Unraveling Bitcoin Smart Contracts