In the world of security audits, careful preparation is not just a preliminary step — it's a strategic imperative that pays dividends throughout the audit process and beyond.

Beyond meeting the immediate objectives of the audit, careful preparation sets the stage for the continuous implementation of development best practices, efficiency, and security.

A proactive approach to audit readiness empowers both security audit teams and the development teams soliciting their services. In particular, effective preparation streamlines the efforts of security audit teams, while reinforcing and requiring best practices from development teams.

By focusing on the following key aspects of audit preparedness, projects can optimize their time and resources, ensuring maximum return on their investment in a security audit.

1. Develop and Maintain Up-to-Date Project Documentation

  • Code Comments: Thorough code documentation, encompassing every function and entry point, provides auditors with necessary insight and a roadmap for understanding the intended functionality of each component.

  • Design Specification: Detailed information about the system's design and requirements helps auditors verify correct code implementation, adherence to specifications, and prevents assumptions that may lead to overlooked security vulnerabilities.

  • Developer Documentation: A comprehensive overview of the system, including architectural diagrams and developer onboarding guides, aids auditing teams in assessing in-scope components and understanding the system's expected behavior.

  • User Documentation: Comprehensive user documentation ensures secure and intended user interactions, guiding auditors through the system.

2. Simplify Code and Minimize Unnecessary Complexity

Complexity is the enemy of both security and understanding. By minimizing unnecessary intricacies and implementing only essential features, projects reduce the potential attack surface of their codebase, and render themselves both stronger and easier to maintain.

3. Implement Test Coverage and Test-Driven Development

A robust test suite, covering success and failure cases, identifies potential edge cases, guards against errors and bugs, and mitigates vulnerabilities. Providing clear instructions for running tests via a single command ensures seamless integration into the audit process.

4. Manage and Update Dependencies

Utilizing audited and well-maintained dependencies reduces the attack surface. Outdated or unmaintained dependencies pose security risks and should be addressed prior to a security audit.

Dependency management tools can be platform/language-specific. Many languages come with their own dependency auditing tools, such as NPM audit for JavaScript and Rust cargo-audit for Rust. Popular and recommended tools that work on multiple languages include OWASP dependency-check and "Snyk Open Source".

Although these tools are beneficial, it's important to note that there is no tool that can completely eliminate all supply-chain security threats. Tools also have their limitations and flaws so dependency management requires a recurring manual review of dependencies as part of the security due diligence process.

5. Identify a Stable Audit Target in the Development Roadmap

Conducting a security audit at a milestone where the system version is complete and no major changes are expected ensures a focused examination. The audit should concentrate on a single stable Git commit of the coded implementation.

6. Pre-Audit Checklist

In order to conduct a robust and comprehensive security audit, development teams should be prepared to provide auditing teams with all the items on the below checklist, at least one week prior to the scheduled audit start date:

  • A URL of the repository containing the source code

  • The release branch and commit hash to be reviewed

  • An explicit list of files in scope and out of scope for the security audit

  • Robust and comprehensive documentation describing the intended functionality of the system

Any additional information, including primary areas of concern and key risks, previous audit reports, clear instructions on setting up the system and running tests, a test coverage report, and the output generated by running the test suite will aid and maximize the auditing team’s efforts.

Finally, it’s important to remember that changes to the audit target after the beginning of the audit are prohibited as they hinder the team’s ability to conduct a comprehensive review.

By adhering to this comprehensive guide, projects set the stage for a successful security audit and lay the foundations for enduring security and development excellence!