Demystifying Smart Contracts Security Audits: Best Practices and Emerging Trends

April 20, 2023

What are smart contracts?

Smart contracts are self-executing contracts that run on blockchain networks, enabling automated and decentralised transactions without the need for intermediaries. They are typically written in code and stored on a blockchain, making them immutable and transparent. Smart contracts are designed to facilitate trust and efficiency in various industries, such as finance, supply chain management, real estate, and more. They have gained popularity due to their potential to streamline business processes, reduce costs, and eliminate the need for intermediaries in transactions.

Smart contracts have gained significant traction in various industries, offering automated and decentralised solutions for numerous use cases. However, as with any technology, smart contracts are not immune to security risks and vulnerabilities. To ensure the integrity and security of smart contracts, comprehensive security audits are essential. In this article, we will explore best practices and emerging trends in smart contracts security audits to help developers and businesses effectively safeguard their smart contracts.

Why do you need a smart contract security audit?

Smart contracts are executed on blockchain networks, making them transparent, immutable, and resistant to tampering. However, they are still susceptible to various security risks, such as coding errors, vulnerabilities, and malicious attacks. Security audits play a crucial role in identifying and addressing these risks, ensuring that smart contracts function as intended, and protecting the interests of stakeholders, including investors, users, and businesses.

Types of Smart Contract Security Audits:

There are several types of security audits that can be performed on smart contracts, including:

  • code reviews
  • vulnerability assessments
  • penetration testing

Code reviews involve in-depth examination of the smart contract's source code to identify coding errors, vulnerabilities and best coding practices.

Vulnerability assessments aim to identify potential weaknesses in the smart contract's design, implementation and deployment.

Penetration testing involves actively testing the smart contract for vulnerabilities by simulating real-world attacks.

A combination of these types of audits provides a multi-faceted approach to smart contract security.

Best Practices for Smart Contract Security Audits:

Conducting smart contract security audits requires following best practices and guidelines to ensure thorough assessments:

  • using a combination of manual and automated testing approaches,
  • using threat modelling to identify potential attack vectors,
  • following secure coding practices, such as input validation, proper use of libraries, and secure data storage.

It's crucial to adopt a comprehensive and systematic approach to smart contract audits, considering both the technical and business aspects of smart contract security.

Common Vulnerabilities in Smart Contracts:

Smart contracts can be vulnerable to various types of attacks, such as reentrancy attacks, integer overflow/underflow, unauthorised access, and front-running.

  • Reentrancy attacks occur when a contract is re-entered before the previous call has completed, allowing an attacker to repeatedly drain funds.
  • Integer overflow/underflow can lead to unexpected behaviours, resulting in unintended consequences.
  • Unauthorised access can occur due to poor access control mechanisms, allowing unauthorised users to execute functions or modify data.
  • Front-running involves manipulating transaction order to gain an unfair advantage. Identifying and addressing these vulnerabilities during security audits is critical to ensuring the security of smart contracts.

Tools and Technologies for Smart Contract Security Audits:

There are various tools, frameworks, and technologies available for conducting smart contract security audits:

  • Static analysis tools, such as Mythril and Slither, analyse smart contract source code to identify potential vulnerabilities,
  • Dynamic analysis tools, such as Ganache and Truffle, help simulate and test smart contracts in a live environment,
  • Vulnerability scanners, such as Oyente and Securify, automate the detection of vulnerabilities.

However, it's essential to understand the features, limitations, and best practices of these tools and technologies and use them judiciously as part of a comprehensive audit process.

Compliance and Regulatory Considerations:

Compliance and regulatory aspects are crucial considerations in smart contract security audits, particularly in industries with specific regulations, such as finance and healthcare. Organisations must ensure that their smart contracts comply with relevant industry-specific regulations, standards, and guidelines. Examples include the General Data Protection Regulation (GDPR) in the European Union, the Financial Action Task Force (FATF) guidelines for anti-money laundering for example.



In conclusion, smart contract security audit is a critical aspect of ensuring the integrity, reliability, and trustworthiness of smart contracts running on blockchain networks. By thoroughly assessing and identifying potential vulnerabilities in smart contracts, businesses and individuals can proactively mitigate risks and protect their digital assets. With the increasing adoption of smart contracts in various industries, the need for robust security auditing practices cannot be overstated. From understanding the basics of smart contracts and their potential benefits to following best practices and engaging with reputable penetration testing companies, businesses can take proactive measures to enhance the security of their smart contracts and mitigate potential risks. Stay informed, implement best practices, and work with experts to ensure the security of your smart contracts in the ever-evolving landscape of blockchain technology.