VeriChain: A Formal Verification Framework for Detecting Vulnerabilities in Blockchain Smart Contracts

Abstract

With the help of pact technology, a program that has been developed, the smart contract can take place between two or more entities without any third-party actor. Although smart contracts provide transparency and efficiency, security flaws in smart contracts have resulted in costly attacks, including re-entrancy, integer overflows, and access control violations. Current tools for intelligent contract verification, such as Mythril, Oyente, and Securify, mainly apply symbolic execution, taint analysis, and pattern matching to identify vulnerabilities. However, these tools have many false positives, take a lot of time to execute, and don't scale efficiently with large numbers of contracts. In this context, the paper presents VeriChain. This formal verification framework combines Control Flow Graph (CFG) analysis, symbolic execution, and static analysis to improve vulnerability detection and tackle the challenges above. VeriChain systematically constructs the contract’s Control Flow Graph (CFG), explores CFG execution paths with symbolic execution, and employs a set of rules for performing rule-based static analysis that can uncover vulnerabilities. Using CFG-based dependency tracking, VeriChain achieves enhanced analysis of dependencies among functions and coverage of execution paths, thereby reducing the number of false positives while achieving accurate detection results. The experimental results show that VeriChain obtains 98.3% detection accuracy, higher than Mythril, Oyente, and Securify. Compared to existing tools, VeriChain has a much lower false-positive rate (1 false alarm) and a much faster execution time (Running in only 2.3 seconds). This framework gives a structured security assessment by categorizing the vulnerabilities according to severity and execution traces, ensuring that the smart contracts are accessed under heavy security verification pre-deployment. With its ability to accomplish highly accurate results efficiently whilst providing structured ways to report on security, VeriChain will be an influential component in delivering safe, innovative contract launches to decentralized applications for blockchain developers and security analysts.