Secure Code Review

Secure code review is the process of reviewing the source code of a software application to identify and eliminate potential security vulnerabilities. It ensures that best coding practices are adhered to and minimizes the chance of data loss, unauthorized access, or injection attack.

A software application’s security can be enhanced through a robust, secure code review practice, which can either be done manually or using automated tools. It is also one of the most critical parts of the software development life cycle (SDLC).

Manual code review: It enables a better comprehension of the code in its context, allowing reviewers to detect logical and design issues that automated tools are unlikely to address. But it can be a long and costly process as well.
Automated code review: Quickly scans large volumes of code to identify common vulnerabilities and coding errors. It is fast and saves time but may be unable to detect intricate or dependency-specific vulnerabilities.

A combination of both methods is often the most effective approach. It leverages the strengths of each, ensuring a more thorough and productive review process while mitigating the weaknesses of each approach.

Why Is Secure Code Review So Important?

Secure source code review provides significant benefits if employed wisely in the development lifecycle.

Prevents security breaches: There are lower chances of security attacks or breaches since it largely identifies and rectifies most of the vulnerabilities before deployment.
Cost-effective: Discovering and fixing security flaws early in the development lifecycle is far cheaper than fixing them after deployment or a security incident.
Compliance: Secure code reviews help to ensure the application complies with industry regulation standards.
Overall code quality improvement: Improves security and helps enhance the code quality by making it maintainable, efficient, and less prone to bugs.
Risk mitigation: Helps minimize security risks by identifying vulnerabilities early and allowing your application less exposure to attacks.

Essential Concepts in Secure Code Review

It’s important to understand key concepts and terms that play a vital role in the process to effectively conduct a secure code review.

Static analysis: Reviewing source code without executing it, using automated tools to detect potential security flaws.
Dynamic analysis: Software applications will be tested while running to identify vulnerabilities that can only be discovered during execution.
Manual review: The manual process of scrutinizing code for vulnerabilities by experts where automated tools might be missed.
Threat modeling: Identify potential security issues earlier in the design stage to help streamline the code review process.
OWASP Top 10: This is a list of the top 10 most indispensable web application security risks that serve as a guide to uncovering vulnerabilities during secure code review.

What Does a Secure Code Review Process Look Like?

A secure code review process typically follows structured stages to identify, address, and mitigate vulnerabilities in the code. Below is a step-by-step breakdown of the process:

1. Preparation stage

Set clear objectives: Identify the code that needs to be reviewed and set up the review goals and objectives.
Gather resources: Assure the necessary documentation access has been provided to the reviewer.

2. Submit code for review

Code change submission: Developers submit code changes as part of a pull request (PR) or a formal code review request.
Contextual information: Developers provide explanations for complex logic, code changes, or security-related decisions to give reviewers a clear understanding.

3. Running the inceptive automated scan

Run SAST and DAST analysis tools: Prior to manual review, use secure code review tools like SAST and DAST to discover known vulnerabilities, coding violations, and potential issues.
Categorize findings: Based on the severity of the vulnerabilities, they should be prioritized, and the high-risk vulnerabilities must be addressed first.

4. Manual code review

Focus areas: Reviewing of high-risk areas like authentication and authorization logic
Security best practices: Assure adherence to security best practices and use of secure frameworks, libraries, etc.

5. Collaborative review

Peer review: The review is conducted collaboratively with a security expert or a developer.
Feedback loop: Developers revise or refactor the code based on reviewer feedback to address identified issues and improve quality.

6. Remediation

Code corrections: Developers fix identified vulnerabilities and improve code quality based on the review findings.
Retest: The revised code should undergo testing to ensure the expected behavior is met.

7. Verification and sign-off

Verification: Ensuring all security issues have been remediated and the code meets the organization’s security standards.
Sign-off: When the review process passes, it will be flagged and approved for deployment.

8. Post-review documentation

Document the findings: Maintaining a detailed record of identified vulnerabilities and remediation steps that could be used as a reference in the future.
Continuous learning: Frequently update teams on new security vulnerabilities and techniques for secure coding to continuously improve security awareness and practices.

Best Practices in Secure Code Review

In order to optimize the advantages of having secure code reviews, it is paramount to observe the best practices that make sure that the reviews are both comprehensive and effective. Below are some key best practices for an effective, secure code review process:

Adhere to secure coding guidelines.
Break down the code into smaller sections for review to avoid overlooking vulnerabilities.
Use SAST and DAST methods to assist in locating views quickly to determine vulnerabilities.
Focus on reviewing critical parts of the code, such as authentication, authorization, input validation, and data processing logic.
Identify potential security risks early in the development process through threat modeling.
Document the vulnerabilities that were discovered and the remedial actions undertaken to close the gaps.
Update secure coding practices and review procedures from time to time to remain relevant to new threats.

Conclusion

In modern software development, secure code review is essential for identifying and addressing potential security risks early in the development lifecycle. This proactive approach enhances software quality and efficiency by reducing costs and mitigating risks through regular reviews, thorough documentation, and continuous improvement. Furthermore, implementing secure code review practices safeguards sensitive customer data and ensures compliance with regulatory standards.