Smart contracts are the most invaluable tools in the domain of blockchain and web3. The blocks of self-executing code run on a blockchain network and have introduced a paradigm shift in the uses of blockchain technology. However, smart contracts are vulnerable to code errors, syntax errors, business logic errors, and social engineering attacks by hackers. Let us find out the most popular smart contract auditing tools that can help you save time and cost in safeguarding your smart contracts.

Therefore, a smart contract analysis tool is a mandatory requirement for smart contract development lifecycles. Smart contracts serve as the core elements for blockchain and web3 applications, which safeguard the financial assets of users. Security of smart contracts is the most important priority for encouraging the adoption of blockchain and web3 technologies. Why would users trust smart contract-based applications that cannot safeguard their valuable assets?

Security breaches of smart contracts can lead to monetary losses as well as damage to the reputation of blockchain protocols. On top of that, smart contract transactions are immutable once verified on the blockchain. As a result, you could not recover from the loss of assets due to smart contract security breaches. 

Therefore, the top smart contracts auditing tools are essential for evaluating the code to find flaws and evaluate the resilience of smart code before deploying on blockchain. You could rely on independent smart contract audit firms to evaluate the posture of security in smart contracts. However, you would have to go through multiple challenges and a time-consuming process to find smart contract audit firms

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What are the Most Popular Smart Contract Auditing Tools?

The immutability of smart contracts calls for comprehensive audits before deploying on a blockchain network. Once you have completed writing your smart contract code, you can start the process of auditing smart contracts with tools. However, you would have to go through the tedious task of finding user-friendly and secure audit tools. Here is a list of smart contract audit tools that could help you build and deploy secure smart contracts

  • Slither

The first addition among the answers to “What are the best smart contract testing tools?” points at Slither. It is a pioneer in the field of smart contract audit tools that offers a robust API for scripting custom analyzers with ease. The most prominent highlight of Slither is the assurance of optimization for detecting vulnerabilities with lower false-positive rates.

In addition, the average time for executing tests in Slither is lower than one second for each contract. However, the average time required for executing tests with Slither depends on complexity of a smart contract. Slither can help in analyzing contracts created with a Solidity compiler version 0.4 or higher. As a result, it could address the requirements of a broad collection of existing contracts. 

Slither is better than a free smart contract audit tool as it supports easier integration in a CI/CD pipeline. It could provide the value of automation in security testing and could deliver better ease of usability to all developers. Slither could discover different types of vulnerabilities in smart contracts, such as suicidal functions, reentrancy vulnerabilities, state variables without initialization, and storage variables. 

Furthermore, Slither could also discover vulnerabilities in quality of source code alongside code optimizations, which lead to higher gas fees. Most important of all, Slither also introduces new upgrades that empower it to conduct better assessments and find different vulnerabilities. 

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  • Mythril

The next addition among the best smart contracts auditing tools is Mythril. It was developed using Python programming language by ConsenSys and offers easy installation through ‘pip.’ The tool utilizes the latest analysis techniques, including taint analysis and symbolic execution, among other techniques. 

Mythril also supports analysis of smart contracts on different blockchain networks other than Ethereum. It only relies on EVM byte code for smart contract analysis. One of the foremost features of Mythril is its ease of use. You can use only the address of a deployed contract for analysis. 

Mythril is one of the popular tools for smart contract audits, as it uses a broad range of techniques for discovering vulnerabilities. It is a trusted tool for auditing smart contracts to find vulnerabilities such as timestamping, transaction order dependency, unchecked math, reentrancy, and unchecked calls. ConsenSys also offers Mythril as a SaaS solution, which simplifies the job of blockchain developers and security professionals. On the other hand, Mythril presents setbacks, such as limitations in discovering business logic errors.

  • MadMax

The collection of popular tools for smart contract audits also includes MadMax. It is a unique choice among top smart contracts auditing tools for identifying the vulnerabilities associated with gas consumption. MadMax utilizes techniques such as control flow analysis and static dataflow analysis for identifying smart contract vulnerabilities. 

MadMax can detect issues such as integer overflows, unbounded mass operations, and non-isolated calls or wallet griefing. The limitation of MadMax points to the limited list of vulnerabilities you can detect with the tool. You would have to use MadMax with other auditing tools to discover more vulnerabilities.

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  • Manticore 

Manticore is also a prominent entry among smart contract auditing tools, which uses an execution-based approach for detecting smart contract vulnerabilities. It has been developed with Python programming language, and you can find it in the default repository of Python.

Manticore is a top alternative to any free smart contract audit tool, as it can help in scanning Ethereum-based programs or smart contract binaries. In addition, it could help in assessment of x86/64 and ARM binaries. The ability to run a symbolic execution on a smart contract could help in improving the code coverage for smart contracts. 

Symbolic execution technique ensures a better probability of finding vulnerabilities with Manticore. However, it presents setbacks in the form of limitations for identifying vulnerabilities in business logic. On the other hand, it could support developers in planning safeguards against vulnerabilities such as invalid instructions, dangerous external calls, integer overflow, uninitialized storage, reentrancy, and dangerous delegate calls.

  • Securify 

Securify is a credible smart contract analysis tool developed with a collaboration between ChainSecurity and the Ethereum Foundation. It can help in analyzing smart contracts that have been compiled with Solidity version 0.5.8 or more. The tool could offer full automation for the security analyzer of Ethereum smart contracts that could prove whether the behavior of a smart contract is safe or dangerous. 

The working mechanism of Securify involves two distinct aspects. First of all, it starts the analysis of the dependency structure of the contract for extracting exact semantic information from the code. The next step of the working mechanism of Securify involves an assessment of the compliance and violation patterns to check different circumstances for validity of smart contracts. In addition, all the patterns in the tool are offered in a domain-specific language, which guarantees more flexibility. On the other hand, Securify could not identify numerical vulnerabilities like overflows.

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  • Oyente

The reputation of Oyente as one of the popular smart contract auditing tools emerges from the fact that it is an early pioneer in the field. It is the ideal answer to “What are the best smart contract testing tools?” as it is the foundation for many other popular smart contract audit tools. Oyente helps in identifying execution traces in which transaction order could affect Ether flow. In addition, it can help in finding timestamp dependency, reentrancy, and identification of exceptions raised by calls. 

Oyente offers easier usability with the flexibility of using it as a command-line tool and also a web-based interface. At the same time, it presents limitations as it could discover only a few issues. On the positive side, developers can use the tool in the CI/CD environment, which helps in reducing the probability of missing vulnerabilities. For example, it could provide better effectiveness in discovering integer overflow vulnerabilities and could complement other smart contract auditing tools.

  • Remix IDE Plugin 

Suppose you want to find something out-of-the-box in your search for a smart contract analysis tool, the Remix IDE plugin for static analysis. The tool is an ideal option for smart contract developers rather than smart contract auditors. It is not a dedicated smart contract auditing tool. 

On the other hand, it is a collection of tools that support integration into VScode and Remix IDE. The plugins can help developers in detecting vulnerabilities before the compilation. Generally, the plugins utilize static analysis alongside pattern-matching techniques for detecting vulnerabilities during the programming stage. 

The popular plugins in Remix IDE for auditing smart contracts include the MythX plugin and Solidity Static Analysis. The plugins could help in discovering vulnerabilities such as inline assembly usage, blockhash usage, and timestamp dependency. Furthermore, the plugins could discover problems associated with code quality issues, optimization problems, and gas consumption issues. The unique highlight of Remix IDE plugins is the facility of plugins for finding business logic errors. 

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  • sFuzz

sFuzz is a popular Ethereum-based fuzzer tool for smart contract audits. It is one of the top smart contracts auditing tools that use the fuzzing technique for evaluating smart contracts. The tool utilizes the AFL fuzzer method featuring lightweight multi-objective adaptive strategies, which target the difficult branches. 

The fuzzer utilizes a feedback-guided adaptive fuzzing model. It works by transforming test generation problems into a specific optimization problem, followed by using a specific type of feedback as an objective function for addressing the optimization issue. 

sFuzz could help in discovering multiple smart contract vulnerabilities such as gasless sends, integer overflow and underflow, timestamp dependency, reentrancy, and dependency on block number. The promising advantage of sFuzz is the assurance of better speed and provision of detecting a wide collection of smart contract vulnerabilities. On top of it, you could also use sFuzz as a supporting tool for other tools that follow symbolic execution for enhancing code coverage.

  • ContractFuzzer

Another popular fuzzer tool among best smart contracts auditing tools is ContractFuzzer. It has effectively used the fuzzing technique to offer better advantages than existing techniques for code analysis and detection of vulnerabilities. The technique involves execution of smart contracts with different inputs to elicit a unique behavior that showcases signs of an existing vulnerability. ContractFuzzer identifies vulnerabilities in Ethereum-based smart contracts that utilize the ABI specifications of smart contracts. 

The smart contract analysis tool helps in defining test oracles for detecting security vulnerabilities. On top of it, ContractFuzzer also models the EVM for logging smart contract runtime behaviors and analysis of the logs for reporting security vulnerabilities. However, it is also important to note the limitations of ContractFuzzer in detecting vulnerabilities due to higher false-negative rates. 

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  • MythX

MythX is another popular cloud-based static analysis tool for smart contracts. It utilizes symbolic analysis techniques for detecting flaws in smart contracts. One of the most prominent highlights of MythX as a popular smart contract auditing tool is the cloud-based accessibility. 

MythX is a trusted answer to “What are the best smart contract testing tools?” as it supports every major programming environment, such as Remix, VSCode, and Truffle. In addition, it is also compatible with smart contracts programmed in Solidity and Vyper. The strengths of MythX are evident in the facility of multiple security analysis tools, such as taint analysis, manual review, fuzzing, and symbolic execution. 

MythX also supports the automatic generation of exploits for detected vulnerabilities that can help developers view the potential impact of vulnerabilities. As a result, developers could also test the remediation efforts for detected vulnerabilities. One of the distinct highlights of the smart contract analysis tool is the fact that almost everyone in the Ethereum development community uses MythX. It can help in improving smart contract security audits, albeit with limitations like the requirement of a subscription. 

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The outline of the top smart contracts auditing tools shows that you can access helpful resources for independent smart contract audits. Each tool has unique strengths and limitations for smart contract testing and could serve as the right choice for certain use cases. Smart contract audits are a necessary aspect for verification of smart contract quality before deploying them on blockchain. Learn more about smart contract development and the importance of smart contract security right now.

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