Web Application Security Testing: Strategies and Tools to Identify Vulnerabilities

Every software has bugs. Some errors are only cosmetic in nature, others jeopardize the confidentiality, integrity or availability of the data processed in the software as a vulnerability or security gap. As a digital agency, we therefore work every day on how we can build more secure software using various strategies and tools for security testing and thus satisfy our customers in the long term.

It is important that these security tests can be integrated into the development cycle as early as possible and can be carried out as easily as possible for developers. In recent years, a buzzword has been established for this: Shift-Left. This approach describes that testing should be carried out continuously throughout the development process and not just at the end. That is why in this post we focus on automated approaches and tools, rather than on manual methods such as code reviews and penetration tests, which are of course no less relevant.

Why invest in application security?

Everyone has certainly heard that investments in more IT security are becoming increasingly relevant as the (admittedly very abstract) threat situation grows. But what specific threat scenarios actually exist and what benefits can we derive from tackling these scenarios?

Protecting sensitive data:

Insecure applications and websites are a gateway for criminals to access sensitive data. This may include customer information, financial data, personal identification information, and other sensitive information. Investments in security technologies and practices help protect this data from unauthorized access.

Preventing data loss and downtime:

Security breaches can result in significant data loss and downtime, resulting in financial and reputational damage. By implementing robust security measures, you can minimize the risk of data loss and downtime and ensure business continuity.

Regulatory compliance:

‍Depending on the industry and location, websites and applications are subject to various legal regulations and data protection regulations. Investing in security helps ensure that your systems comply with applicable regulations and avoid potential legal issues.

When is investing in security the most worthwhile?

In Software Development Lifecycle (SDLC) automated (safety) tests play a decisive role, particularly in the development phase. By embedding automated tests early in the cycle, potential security gaps and errors can be identified and resolved as early as the development phase. This not only enables faster time to market, but also significantly reduces costs.

According to Shahadat Hossain, fixing bugs in the development phase is up to 100 times more cost-effective compared to late bug fixes during or after deployment. Investing in automated security testing right from the start in the SDLC therefore pays off not only in terms of safety and quality, but also financially.

From theory to practice

Investments in security testing are a fundamental component of a strategy for minimizing risks. By using proactive code analysis and simulations of real attack scenarios, we can effectively identify and address potential security threats before they cause damage. It is important to understand the differences and individual benefits of both approaches:

Proactive Code Analysis: Static Application Security Testing (SAST)

As the name suggests, static application security testing (SAST) is characterized by analyzing static code for vulnerabilities. The major advantage here is that by analysing all code (known as white box testing), potential vulnerabilities can also be identified that could remain undetected without knowledge of the code and all functionalities when looking at the application from the outside. A practical example of a SAST tool is Semgrep, which carries out automated analyses and helps identify and address safety-critical errors before the software is put into operation.

However, some vulnerabilities are difficult to identify based solely on the code. This is where dynamic safety testing (DAST) comes in.

Simulation of real attack scenarios: Dynamic Application Security Testing (DAST)‍

In contrast to SAST tools, DAST tools generally receive less to no information about the internals of the application (known as Black box testing). This approach therefore tests the application under real operating conditions, similar to the attack methods that a hacker could use. On the one hand, this makes it easier to set up a test, but usually also limits the viewing area of the scanner, which may not reach all functions of the application. Dastardly by Portswigger is an example of a DAST tool that carries out dynamic tests and makes it possible to uncover even those security gaps that only become visible during actual operation of the software.

Summary and Conclusion

By integrating SAST and DAST into our development process, we achieve a thorough and comprehensive security review of our applications. This strategy is not only a key to ensuring security, but also helps protect data integrity and availability.

We would be happy to provide you with advice or to implement automated security tests for your applications! If you would like to see application examples for SAST and DAST, feel free to have a look at this article.