Preventing Ethereum Blockchain Re-Entrancy Attacks Using Smart Mutex Lock Sum

Since the smart contracts are being introduced, they are being subjected to various vulnerabilities. These vulnerabilities pose a major threat to participant's money and cause conflicts. Smart contracts are self executing contracts that use blockchain technology to transfer values among peers in which there is no control of a central authority to run and execute transactions. Reentrancy, one of the most important vulnerabilities in smart contracts, has caused millions of dollars in financial loss. As technology advances, many reentrancy solutions have been implemented and various detection approaches have been proposed. In this paper, it proposed a “Smart MutexLock” mechanism to prevent Ethereum reentrancy. Since the smart contracts on blockchain platforms like Ethereum do not directly support mutex locks due to their deterministic and asynchronous nature, it have used mutex locks in an effective and secure manner. The mutex mapping is used to keep track of whether a particular address is currently in a transaction to prevent reentrancy. The mutex variable is set to true before any external call, preventing further calls until the transaction is completed. Once the transaction is complete, the mutex variable is set back to false and user is notified to ensure a safe transaction