Blockchain Smart Contract Security

Blockchain Security

Blockchain Security Many studies have begun to explore blockchain security, and Alharby and Moorsel found that common risks in blockchain include 51% attacks, private key custody, criminal activity, double-spending issues, information leakage, and more. In addition, during the transaction process, if the transaction is not executed in the correct order or the miner maliciously modifies the timestamp of the block, the correctness of the smart contract may be affected. There are already related tools to detect, for example, Oyente, smart contract audit services developed by researchers at the National University of Singapore in January 2016, is the first tool to analyze and detect the security of smart contracts, which can analyze smart contracts and return possible bug attacks.

At present, the main contract detection tools are: Slither, Contract-Library, Echidna, Manticore, Oyente, Securify, SmartCheck, Octopus, sFuzz, Vertigo, etc. Most of the detection methods of these tools are to compare the vulnerability code collected in the current database to judge whether it is consistent with the content of the database. However, there are limitations to the vulnerabilities related to cross-contract function calls.

Smart Contract Vulnerability Scanning and Auditing

Vulnerabilities due to smart contract design flaws can also cause huge losses, and once triggered, the contract cannot be changed or stopped, smart contract audit and sometimes a small bug on a smart contract can break the entire protocol. For example, the stablecoin protocol Beanstalk Farms was hacked to steal more than $80 million worth of cryptocurrencies, resulting in losses of more than $180 million; on June 24, 2022, the cross-chain bridge Horizon between Ethereum and Harmony was attacked, causing losses The amount is about 100 million US dollars; a report released by the blockchain research organization Chainalysis in 2021 pointed out that the total amount of assets lost by victims due to encryption hacking incidents that year was as high as 7.7 billion US dollars!

It can be seen that the security of smart contracts is particularly important on the blockchain. If there are defects and mistakes in various codes and programs covered in smart contracts, it will lead to security loopholes, which will affect the operation of the entire project or system. . At present, some companies have launched the “Blockchain Contract Audit” (BCA), which provides relevant suggestions and corrections for blockchain deployment programs and smart contract loopholes, and provides corresponding review reports for enterprises and projects. Issue an extra layer of security. Taking smart contract security auditing as an example, it includes security auditing and defense deployment services such as pre-launch code security auditing of Web3 projects, risk warning and monitoring during project operation, and recovery of stolen encrypted assets. Such an audit is especially important for Party A who entrusts Party B to develop smart contracts (such as DeFi, NFT, GameFi, etc.), and testing by a third party can reduce relative risks.

In general, the security issues that we need to pay attention to in the development of programs in the past are also the same in the application of blockchain. Different from traditional information security, when smart contracts are programmed asset transfer on the blockchain platform, and these assets are all cryptocurrencies (digital assets), they must bear the risk of trading cryptocurrencies, and usually Compared with traditional information security loopholes, the property loss is more and the scope of influence is larger. Our research on the security of bsc smart contract audit is not yet mature, the limitations of blockchain privacy security technology, etc., and there are currently no clear regulations, so it is difficult to determine the attribution of damages and liabilities. This part is also a problem that must be dealt with cautiously at present.