Website source code audit: why is it important to do it?

By auditing the source code of a website, vulnerabilities can be detected before they are exploited and corrected in time

Insecure design is one of the main security risks on a website. In fact, in the latest edition of the Top 10 web application vulnerabilities compiled by the OWASP foundation, a global benchmark in cybersecurity, insecure design ranked fourth in the list of vulnerabilities. Why is this? Malicious actors scan web code for weaknesses and vulnerabilities to exploit them and carry out successful cyberattacks against companies.

For this reason, cybersecurity specialists recommend implementing cybersecurity policies from the design stage and carrying out a recurring audit of a website’s source code to prevent unnoticed code flaws from opening the door to criminals.

Below, we will address the keys to auditing a website’s source code, as well as its benefits for companies.

1. Why is it essential to carry out an audit of a website’s source code?

As we pointed out before, the insecure design of web applications is one of the main threats to their security. Although there are lists of good practices in the field of secure development, the truth is that:

• Some developers do not have specific training in cybersecurity and focus all their efforts on the design of the website, relegating its security.
• It is common to use previous code that may suffer from undetected vulnerabilities or become obsolete.
• Programs and programming languages are constantly changing, so it is important to continually audit the code so that it does not become obsolete or present security deficiencies.
• In today’s fully digital world, where there is a high demand for website creation, development times are getting shorter and sometimes, little priority is given to application security.
• During code development, errors can be made that go unnoticed unless an audit of the source code of a website is carried out.
• It is a widespread practice to use third-party libraries and dependencies when developing websites, which means that a vulnerability in one of these components can affect a company’s website.
• Throughout the life cycle of a website, several developers can add or modify its code, which can have security consequences.
• New artificial intelligence systems that help to create code quickly can add vulnerabilities to the generated code, which is why it is necessary to review it from a security point of view.

In this scenario, auditing a website’s source code helps to detect and fix vulnerabilities before hostile actors detect and successfully exploit them.

2. How is a website source code audit performed?

As with many other cybersecurity services, when it comes to performing a comprehensive source code audit, the use of automated tools and the knowledge and experience of specialized professionals come into play.

Thus, in an audit of a website’s source code, it is necessary to perform automated static analysis of the source code (SAST) using security solutions designed for this purpose. In this way, security problems in a website’s code can be detected automatically without having to execute it.

Subsequently, experts in carrying out source code audits analyze all the information generated by these tools and:

• Filter out false positives.
• Detect false negatives thanks to their specialized knowledge.
• List and describe the vulnerabilities found in the code, including those present in third-party components.
• Point out bad development practices and try to correct them in the future.
• Advise web developers to help them understand the vulnerabilities.
• Propose solutions to fix security flaws.
• They feed specific rules into the SAST tools for each project to detect common vulnerabilities in the development teams.

3. When should an audit of a website’s source code be carried out?

It is essential to carry out an audit of a website’s source code before it is used, especially if it is not for purely internal use and is, therefore, intended to be used by customers and other users.

It is also vitally important to carry out a periodic audit of the source code of a website. Why? Website codes can change. Therefore, throughout the entire life cycle of a website, it is important to analyze its code to ensure that the changes do not have negative consequences in terms of security.

To this we must add the fact that auditing the code can detect vulnerabilities in third-party libraries and dependencies used in the development of the website in order to fix them before they are successfully exploited.

If we use the Shift-left methodology, the sooner the code and its design can be analyzed, the sooner a possible structural change that could affect a large part of the application’s development can be addressed, saving human and material effort.

4. Is it important to carry out an audit of the source code of a website when it has not been developed in-house?

An audit of a website’s source code is not only a cybersecurity service with great added value for companies that develop websites but also for those that have websites that have not been developed in-house.

Thus, companies that use websites developed by third parties should also carry out a periodic audit of the source code to guarantee an adequate level of security and avoid serious incidents.

Cyberattacks against corporate websites can result in data leaks exposing critical information about companies, their customers or their employees. This is why it is so important for companies that outsource websites to third parties to carry out code audits that allow them to gain an in-depth understanding of the security status of the codes.

Similarly, privacy analyses that review how user and customer data is being processed can be used to determine whether a third-party code is processing the data correctly or, if not, whether there is a leak to servers, files or, in short, unofficial data repositories that do not belong to the company itself.

5. What are the benefits of an audit of a website’s source code?

Taking into account what we have been discussing in this article, we can point out some of the great benefits that an audit of the source code of a website has for companies:

• To prevent the code of a website from presenting vulnerabilities that malicious actors can exploit.
• To ensure that developers carry out secure development practices.
• To analyze in depth the execution flows of the source code.
• Ensure that websites are secure from the design stage and throughout their life cycle.
• Prevent security incidents that affect the functioning of a website or that result in the theft of confidential information hosted on it, such as private customer data.
• Avoid the economic, reputational and legal consequences of a website being attacked because its code presents security problems.
• Reduce the costs of website development and maintenance.

6. Conclusion: a practice that can save major problems

In short, auditing website source code is an essential practice for anticipating hostile actors, detecting vulnerabilities that can be exploited and remedying them.

In addition, source code audits help to guarantee an optimal level of website security from the design stage throughout the entire life cycle and prevent serious security incidents.

If you have any questions about source code audits, you can find all the information on our service page.