SolSec Labs is a web-based application that provides interactive training labs for blockchain developers, especially students eager to learn more about smart contract security to gain practical knowledge ( <xref ref-type="fig" rid="fig1" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Fig. 1</xref> ). It teaches solidity and smart contract security skills through hands-on experience. The easy-to-understand environment enables students and early developers to immediately apply newly learned secure coding practices to their ongoing projects. Currently, it consists of a total of 10 labs crafted using examples taken from the most severe real-world vulnerabilities. Every lab teaches developers about the related vulnerability; exploitation methods; preventive and remediation measures; and, finally, a step-by-step list of lab tasks to perform to secure the presented vulnerable code.
Smart Grid Security and Resilience
Security and Verification in Computing
Advancements in Semiconductor Devices and Circuit Design
Zihan Zhao, Sidi Mohamed Beillahi, Ryan Song, Yuxi Cai · 6 authors
This paper presents SigVM, the first blockchain virtual machine that extends EVM to support an event-driven execution model, enabling developers to build truly decentralized smart contracts. Contracts in SigVM can emit signal events, on which other contracts can listen. Once an event is triggered, corresponding handler functions are automatically executed as signal transactions. We build an end-to-end blockchain platform SigChain and a contract language compiler SigSolid to realize the potential of SigVM. Experimental results show that our benchmark applications can be reimplemented with SigVM in a truly decentralized way, eliminating the dependency on centralized and unreliable mechanisms like off-chain relay servers. The development effort of reimplementing these contracts with SigVM is small, i.e., we modified on average 3.17% of the contract code. The runtime and the gas overhead of SigVM on these contracts is negligible.
Stefanos Chaliasos, Arthur Gervais, Benjamin Livshits
The Solidity programming language is the most widely used language for smart contract development. Improving smart contracts’ correctness, security, and performance has been the driving force for research in vulnerability detection, program analysis, and compiler techniques for Solidity. Similar to system-level languages such as C, Solidity enables the embedding of low-level code in programs, in the form of inline assembly code. Developers use inline assembly for low-level optimizations, extending the Solidity language through libraries, and using blockchain-specific opcodes only available through inline assembly. Nevertheless, inline assembly fragments are not well understood by an average developer and can introduce security threats as well as affect the optimizations that can be applied to programs by the compiler; it also significantly limits the effectiveness of source code static analyzers that operate on the Solidity level. A better understanding of how inline assembly is used in practice could in turn increase the performance, security, and support for inline assembly in Solidity. This paper presents a large-scale quantitative study of the use of inline assembly in 6.8M smart contracts deployed on the Ethereum blockchain. We find that 23% of the analyzed smart contracts contain inline assembly code, and that the use of inline assembly has become more widespread over time. We further performed a manual qualitative analysis for identifying usage patterns of inline assembly in Solidity smart contracts. Our findings are intended to help practitioners understand when they should use inline assembly and guide developers of Solidity tools in prioritizing which parts of inline assembly to implement first. Finally, the insights of this study could be used to enhance the Solidity language, improve the Solidity compiler, and to open up new research directions by driving future researchers to build appropriate methods and techniques for replacing inline assembly in Solidity programs when there is no real necessity to use it.
Javier Godoy, Juan Pablo Galeotti, Diego Garbervetsky, Sebastián Uchitel
Smart contracts are immutable programs deployed on the blockchain that can manage significant assets. Because of this, verification and validation of smart contracts is of vital importance. Indeed, it is industrial practice to hire independent specialized companies to audit smart contracts before deployment. Auditors typically rely on a combination of tools and experience but still fail to identify problems in smart contracts before deployment, causing significant losses. In this paper, we propose using predicate abstraction to construct models which can be used by auditors to explore and validate smart contact behaviour at the function call level by proposing predicates that expose different aspects of the contract. We propose predicates based on requires clauses and enum-type state variables as a starting point for contract validation and report on an evaluation on two different benchmarks.
Eric Keilty, Keerthi Nelaturu, Bowen Wu, Andreas Veneris
As the popularity of distributed ledger technology and smart contracts continues to grow, so does the number of decentralized applications and their potential exposure to expensive exploits. The need for strong vulnerability detection tools is critical. Move is a recently developed smart contract language with safety and security at the core of its design containing formal verification tools embedded into the language. Currently, these tools can only verify local properties within a single Move function. They cannot verify global properties that result from multiple function executions. In this paper, we introduce VeriMove, an extension of the VeriSolid correct-by-design model checking framework that supports the Move language. We show that model checking is a feasible method to formally verify global properties in Move smart contracts.
As a powerful tool for building framework and autonomous system across various domains, smart contracts are used to maintain security analysis in a better way. However, owing to the decentralised structure of the blockchain on which they are built, a number of concerns have surfaced about weaknesses in their programming, that according to their unique characteristics, might have (and have already had) a very large economic effect. This essay surveys the whole scope of smart contract security issues and the cutting edge of freely accessible security software.
Tommaso Frassetto, Patrick Jauernig, David Koisser, David Kretzler · 7 authors
Smart contracts enable users to execute payments depending on complex program logic. Ethereum is the most notable example of a blockchain that supports smart contracts leveraged for countless applications including games, auctions and financial products. Unfortunately, the traditional method of running contract code on-chain is very expensive, for instance, on the Ethereum platform, fees have dramatically increased, rendering the system unsuitable for complex applications. A prominent solution to address this problem is to execute code off-chain and only use the blockchain as a trust anchor. While there has been significant progress in developing off-chain systems over the last years, current off-chain solutions suffer from various drawbacks including costly blockchain interactions, lack of data privacy, huge capital costs from locked collateral, or supporting only a restricted set of applications. \n \nIn this paper, we present POSE—a practical off-chain protocol for smart contracts that addresses the aforementioned shortcomings of existing solutions. POSE leverages a pool of Trusted Execution Environments (TEEs) to execute the computation efficiently and to swiftly recover from accidental or malicious failures. We show that POSE provides strong security guarantees even if a large subset of parties is corrupted. We evaluate our proof-of-concept implementation with respect to its efficiency and effectiveness.
Smart contracts are self-governed computer programs that run on blockchain to facilitate asset transfer between users within a trustless environment. The absence of contract specifications hinders routine tasks, such as program understanding, debugging, testing, and verification of smart contracts. In this work, we propose a unified specification mining framework to infer specification models from past transaction histories. These include access control models describing high-level authorization rules, program invariants capturing low-level program semantics, and behavior models characterizing interaction patterns allowed by contract implementations. The extracted specification models can be used to perform conformance checking on smart contracts, with the goal of eliminating unforeseen contract quality issues.
The growth in the popularity of smart contracts has been accompanied by a rise in security attacks targeting smart contracts, which have led to financial losses of millions of dollars and erosion of trust. To enable developers discover vulnerabilities in smart contracts, several static analysis tools have been proposed. However, despite the numerous bug-finding tools, security vulnerabilities abound in smart contracts, and developers rely on finding vulnerabilities manually. Our goal in this dissertation study is to expand the space of security vulnerabilities detection by proposing effective static analysis approaches for smart contracts. We study the effectiveness of the existing static analysis tools and propose solutions for security vulnerabilities detection relying on analyzing the dependency of the contract code on user inputs that lead to security vulnerabilities. Our results of evaluating static analysis tools show that existing static tools for smart contracts have significant false-negatives and false-positives. Further, the results show that our first vulnerability detection approach achieves a significant improvement in the effectiveness of detecting vulnerabilities compared to the prior work.
Smart contracts are gaining popularity as a means to support transparent, traceable, and self-executing decentralized applications, which enable the exchange of value in a trustless environment. Developers of smart contracts rely on various libraries, such as OpenZeppelin for Solidity contracts, to improve application quality and reduce development costs. The API documentations of these libraries are important sources of information for developers who are unfamiliar with the APIs. Yet, maintaining high-quality documentations is non-trivial, and errors in documentations may place barriers for developers to learn the correct usages of APIs. In this paper, we propose a technique, DocCon, to detect inconsistencies between documentations and the corresponding code for Solidity smart contract libraries. Our fact-based approach allows inconsistencies of different severity levels to be queried, from a database containing precomputed facts about the API code and documentations. DocCon successfully detected high-priority API documentation errors in popular smart contract libraries, including mismatching parameters, missing requirements, outdated descriptions, etc. Our experiment result shows that DocCon achieves good precision and is applicable to different libraries: 29 and 22 out of our reported 40 errors have been confirmed and fixed by library developers so far.
Smart contracts are self-executing computer programs deployed on blockchain to enable trustworthy exchange of value without the need of a central authority. With the absence of documentation and specifications, routine tasks such as program understanding, maintenance, verification, and validation, remain challenging for smart contracts. In this paper, we propose a dynamic invariant detection tool, InvCon, for Ethereum smart contracts to mitigate this issue. The detected invariants can be used to not only support the reverse engineering of contract specifications, but also enable standard-compliance checking for contract implementations. InvCon provides a Web-based interface and a demonstration video of it is available at: https://youtu.be/Y1QBHjDSMYk.
Ignacio Amores-Sesar, Christian Cachin, Tedeschi, Enrico
Avalanche is a blockchain consensus protocol with exceptionally low latency and high throughput. This has swiftly established the corresponding token as a top-tier cryptocurrency. Avalanche achieves such remarkable metrics by substituting proof of work with a random sampling mechanism. The protocol also differs from Bitcoin, Ethereum, and many others by forming a directed acyclic graph (DAG) instead of a chain. It does not totally order all transactions, establishes a partial order among them, and accepts transactions in the DAG that satisfy specific properties. Such parallelism is widely regarded as a technique that increases the efficiency of consensus. Despite its success, Avalanche consensus lacks a complete abstract specification and a matching formal analysis. To address this drawback, this work provides first a detailed formulation of Avalanche through pseudocode. This includes features that are omitted from the original whitepaper or are only vaguely explained in the documentation. Second, the paper gives an analysis of the formal properties fulfilled by Avalanche in the sense of a generic broadcast protocol that only orders related transactions. Last but not least, the analysis reveals a vulnerability that affects the liveness of the protocol. A possible solution that addresses the problem is also proposed.
Blockchains have seen growing traction with cryptocurrencies reaching a market cap of over 1 trillion dollars, major institution investors taking interests, and global impacts on governments, businesses, and individuals. Also growing significantly is the heterogeneity of the ecosystem where a variety of blockchains co-exist. Cross-chain bridge is a necessary building block in this multi-chain ecosystem. Existing solutions, however, either suffer from performance issues or rely on trust assumptions of committees that significantly lower the security. Recurring attacks against bridges have cost users more than 1.5 billion USD. In this paper, we introduce zkBridge, an efficient cross-chain bridge that guarantees strong security without external trust assumptions. With succinct proofs, zkBridge not only guarantees correctness, but also significantly reduces on-chain verification cost. We propose novel succinct proof protocols that are orders-of-magnitude faster than existing solutions for workload in zkBridge. With a modular design, zkBridge enables a broad spectrum of use cases and capabilities, including message passing, token transferring, and other computational logic operating on state changes from different chains. To demonstrate the practicality of zkBridge, we implemented a prototype bridge from Cosmos to Ethereum, a particularly challenging direction that involves large proof circuits that existing systems cannot efficiently handle. Our evaluation shows that zkBridge achieves practical performance: proof generation takes less than 20 seconds, while verifying proofs on-chain costs less than 230K gas. For completeness, we also implemented and evaluated the direction from Ethereum to other EVM-compatible chains (such as BSC) which involves smaller circuits and incurs much less overhead.
When do classical zero-knowledge protocols remain secure against quantum attacks? In this work, we develop the techniques, tools, and abstractions necessary to answer this question for foundational protocols:1)We prove that the Goldreich-Micali-Wigderson protocol for graph non-isomorphism and the Feige-Shamir protocol for NP remain zero-knowledge against quantum adversaries. At the heart of our proof is a new quantum rewinding technique that enables extracting information from multiple invocations of a quantum adversary without disturbing its state.2)We prove that the Goldreich-Kahan protocol for NP is post-quantum zero knowledge using a simulator that can be seen as a natural quantum extension of the classical simulator.Our results achieve negligible simulation error, appearing to contradict a recent impossibility result due to Chia-Chung-Liu-Yamakawa (FOCS 2021). This brings us to our final contribution:3.We introduce coherent-runtime expected quantum polynomial time, a simulation notion that (a) precisely captures all of our zero-knowledge simulators, (b) cannot break any polynomial hardness assumptions, (c) implies strict polynomial-time ε-simulation and (d) is not subject to the CCLY impossibility. In light of our positive results and the CCLY negative results, we propose coherent-runtime simulation to be the appropriate quantum analogue of classical expected polynomial-time simulation.
Smart contracts are programs which encode business logic and execute on the blockchain. While Ethereum is the most popular blockchain platform for smart contracts, an increasing number of new blockchain platforms are also able to support smart contract execution (e.g., Solana or Cardano). Security vulnerabilities in Ethereum smart contracts have demonstrated that writing secure smart contracts is highly challenging. This is exacerbated by the fact that the exploitation of buggy smart contracts seems disproportionately easier compared to exploiting classic PC software. In this tutorial, we overview a number of smart contract vulnerabilities focusing on the Ethereum ecosystem. We also provide an introduction to the de-facto smart contract programming language Solidity and provide a comprehensive hands-on lab tutorial that involves analyzing vulnerable smart contracts, developing proof-of-concept exploits as well as introducing security analysis tools for testing smart contracts
Mujeeb A. Shittu, Ibukun Olaoluwa Adeniji, Habeeb Shittu, Ifeanyi Simon Opara
This study presents a comprehensive and critical examination of blockchain-assisted secure data exchange within SCADA-controlled power systems, motivated by the growing cybersecurity risks and trust deficits associated with increasingly digitalised and decentralised electricity infrastructures. The primary purpose of the study is to evaluate the extent to which blockchain technologies can enhance the security, integrity, and resilience of SCADA data exchange while remaining compatible with the stringent performance and safety requirements of power system operations. A structured review methodology was adopted to synthesise peer-reviewed literature from power system engineering, cybersecurity, distributed ledger technologies, and related cyber-physical system domains. The analysis systematically examined SCADA communication architectures, data exchange models, blockchain fundamentals, integration paradigms, consensus mechanisms, privacy and access control strategies, interoperability challenges, and empirical pilot implementations across both developed and developing contexts. The findings reveal that conventional SCADA architectures, largely built on centralised trust and legacy protocols, are increasingly inadequate for addressing modern threat landscapes and multi-stakeholder data sharing requirements. Blockchain-assisted architectures—particularly permissioned and hybrid on-chain/off-chain models—demonstrate strong potential to improve data integrity, auditability, non-repudiation, and cross-organisational trust without disrupting real-time control functions. However, the study also identifies persistent challenges related to scalability, interoperability, governance complexity, and human capacity, which constrain large-scale deployment. Empirical evidence from pilot projects further indicates that blockchain is most effective when applied selectively at supervisory and coordination layers rather than within time-critical control loops. The study concludes that blockchain-assisted secure data exchange represents a strategically valuable complement to existing SCADA security mechanisms rather than a standalone solution. It recommends future research on performance-optimised consensus protocols, standardised integration frameworks, and the convergence of blockchain with advanced analytics and artificial intelligence. Policy alignment, capacity development, and context-aware implementation strategies are also essential to support sustainable adoption, particularly in developing power system environments.
These days, businesses, in both online and offline, have started accepting cryptocurrencies as payment methods. Even in countries like <italic>El Salvador</italic>, cryptocurrencies are recognized as fiat currencies. Meanwhile, publicly known, but not patched software vulnerabilities are security threats to not only software users but also to our society in general. As the status of cryptocurrencies has gradually increased, the impact of security vulnerabilities related to cryptocurrencies on our society has increased as well. In this paper, we first analyze vulnerabilities from the two major cryptocurrency vendors of Bitcoin and Ethereum in a quantitative manner with the respect to the CVSS, to see how the vulnerabilities are roughly structured in those systems. Then we introduce a modified AML vulnerability discovery model for the vulnerability datasets from the two vendors, after showing the original AML dose not accurately represent the vulnerability discovery trends on the datasets. The analysis shows that the modified model performs better than the original AML model for the vulnerability datasets from the major cryptocurrencies.
Smart contracts are tempting targets of attacks, as they often hold and manipulate significant financial assets, are immutable after deployment, and have publicly available source code, with assets estimated in the order of millions of dollars being lost in the past due to vulnerabilities. Formal verification is thus a necessity, but smart contracts challenge the existing highly efficient techniques routinely applied in the symbolic verification of software, due to specificities not present in general programming languages. A common feature of existing works in this area is the attempt to reuse off-the-shelf verification tools designed for general programming languages. This reuse can lead to inefficiency and potentially unsound results, as domain translation is required. In this article, we describe a carefully crafted approach that directly models the central aspects of smart contracts natively, going from the contract to its logical representation without intermediary steps. We use the expressive and highly automatable logic of constrained Horn clauses for modeling and instantiate our approach to the Solidity language. A tool implementing our approach, called Solicitous , was developed and integrated into the SMTChecker module of the Solidity compiler solc. We evaluated our approach on an extensive benchmark set containing 22,446 real-world smart contracts deployed on the Ethereum blockchain over a 27-month period. The results show that our approach is able to establish safety of significantly more contracts than comparable, publicly available verification tools, with an order of magnitude increase in the percentage of formally verified contracts.
Smart contracts are the key software components to realize blockchain applications, from single encrypted digital currency to various fields. Due to the immutable nature of blockchain, any bugs or errors will become permanent once published and could lead to huge economic losses. Recently, a great number of security problems have been exposed in smart contracts. It is important to verify the correctness of smart contracts before they are deployed on the blockchain. This paper aims to verify the correctness of smart contracts in Ethereum transactions, and the model checker Spin is adopted for the formal verification of smart contracts in order to ensure their execution with respect to parties’ willingness, as well as their reliable interaction with clients. In this direction, we propose a formal method to construct the models for smart contracts. Then, the method is applied to a study case in the Ethereum commodity market. Finally, a case model is implemented in Spin, which can simulate the process’s execution and verify the properties that are abstracted from the requirements. Compared with existing techniques, formal analysis can verify whether smart contracts comply with the specifications for given behaviors and strengthen the credibility of smart contracts in the transaction.
Ransomware is a type of malicious program or software that encrypts the contents on a hard disc and prevents the users from accessing them unless they pay an amount (called a ransom). Most of the organizations, such as financial institutes and healthcare sectors (i.e., smart healthcare) are targeted by ransomware attacks. Ransomware assaults are among the most frightening types of cyber-attacks, and they are not confined to a specific sector or the countries. Blockchain is a tamper-proof technology, which is more secure, robust and decentralized in nature. Features of blockchain can add more security for detection and mitigation of ransomware more effectively. In this paper, we propose a new blockchain-enabled security framework to detect and defend the ransomware attacks for smart healthcare (in short, BSFR-SH). The conducted security analysis proves the security of the proposed BSFR-SH against the ransomware attacks. The performance of BSFR-SH is significantly better than the other similar existing mechanisms as it achieves better accuracy and F1-score than other compared mechanisms. Furthermore, the practical demonstration of BSFR-SH is provided to estimate the impact on important performance parameters.
Galip Savas Ilgi, Devrim Kayalı, Priscilla Olawale, Binnur Demir Erdem · 6 authors
Last two decades enhancements of the communication technologies have been interpreting the daily lives as well as the academia and multidisciplinary research fields. One of these enhancements is the blockchain technology which has become one of the most popular and attractive topics over the last five years. Blockchain technology has attracted more and more attention from academia and industry recently. Blockchain is defined as a list of data blocks as a publicly distributed ledger, which are linked together using cryptography. In this matter, cryptographic security issues have increased. In recent years, new, advanced intrusion detection and authentication/privacy protection techniques have been designed and developed. Diversity of computer security requirements results in introducing of different kinds of security models. In fact, each security model is an abstraction of a security policy. Formal Methods have a mathematical foundation, and thus, employs techniques and tools based on mathematics and mathematical logic that support the modelling, specification and verification of the systems. This paper provides a critical and detailed review of the recent researches published in recent years in formal verification methods for communication security in blockchain with artificial intelligence applications.
Francesco D’Amato, Joachim Neu, Ertem Nusret Tas, David Tse
The LMD GHOST consensus protocol is a critical component of proof-of-stake Ethereum. In its current form, this protocol is brittle, as evidenced by recent attacks and patching attempts. We propose Goldfish, a new protocol that satisfies key properties required of a drop-in replacement for LMD GHOST: Goldfish is secure in the sleepy model, assuming a majority of the validators follows the protocol. Goldfish is reorg resilient so that honestly produced blocks are guaranteed inclusion in the ledger, and it supports fast confirmation with expected confirmation latency independent of the desired security level. Subsampling validators can improve the communication efficiency of Goldfish, and Goldfish is composable with finality/accountability gadgets. Crucially, Goldfish is structurally similar to LMD GHOST, providing a credible path to adoption in Ethereum. Attacks on LMD GHOST exploit lack of coordination among honest validators, typically provided by a locking mechanism in classical BFT protocols. However, locking requires votes from a quorum of all participants and is not compatible with fluctuating participation. Goldfish is powered by a novel coordination mechanism to synchronize the honest validators' actions. Experiments with our prototype implementation of Goldfish suggest practicality.