(Last Updated On: January 25, 2022)

Application security testing (AST) plays a crucial role in any software’s development life cycle. It can mitigate many risks and vulnerabilities, such as data leaks, theft of trade secrets, intellectual property loss, and many other dreadful cyber attacks. This article will go over the basics of DAST, how you can benefit from this type of testing, and provide you with a checklist that you can use to perform your very own DAST. We will also leave you with some tips and best practices to follow for developing secure applications.

What is DAST?

DAST is an acronym for Dynamic Application Security Testing. It is the most effective type of AST and works by testing applications while they are running in their live environment. This type of testing can be used to identify security issues that may not be found during the traditional software development life cycle (SDLC) such as design, coding, and unit testing.

Why is application security testing important?

The main reason why application security testing is important is that it can help organizations identify and mitigate vulnerabilities before they are exploited by malicious actors. A study conducted by Ponemon Institute reported that a data breach, on average, cost $148 per record stolen in 2017. These numbers continue to rise each year as cybercriminals get more skilled and the number of stolen documents skyrocket.

Benefits of DAST

DAST can provide a broad and deep understanding of how secure your application really is, which means that it will highlight security issues before they become serious problems for you and your customers. DAST is performed throughout the development of your application and so you get to be confident going forward in the next stage of development that no security flaws were left unattended in the previous stages.

The main benefits of DAST include:

  • Identifying vulnerabilities in their early stages
  • Prioritising remediation efforts
  • Faster development cycles and releases by catching errors early on
  • Reducing the overall cost of deployment by pinpointing issues before they get deployed for customer use
  • In-depth prior knowledge of the application to be tested is not required
  • Fewer false positives

It is important to note that DAST can only be performed using dynamic methods, which means it will not find vulnerabilities in the source code. It will instead help you identify issues while your application is running (in its live environment). This type of testing should therefore always be paired with static code analysis (SCA) in order to get a more complete and accurate assessment of your application’s security posture.

Checklist to Perform DAST

The checklist to perform DAST includes the following:

  1. Identify and map out all entry points into your application (this is also known as entry points mapping)
  2. Map out the functionalities of your application (the features that it offers to users) and identify any potential business logic flaws, such as insecure direct object references or cross-site request forgery (CSRF), etc.
  3. Identify all client-side controls you can use to protect against attacks, such as Content Security Policy (CSP), input validation, and output encoding
  4. Ensure that all user-provided data is validated and properly escaped before being stored or displayed in the application
  5. Decide which tools you will be using for this task (for example, Astra Security, WebScarab, Burp Suite, etc.) and familiarise yourself with them
  6. Perform the tests in a test environment first. If you encounter any issues that interrupt the functionality of your application, fix them before moving to the next stage of production

If you are performing DAST manually, follow these steps for each entry point into your application

If you are using a tool to perform DAST, then make sure to configure the tool according to your needs and run it against your application

Best Practises for Developing Secure Applications

In order to develop secure applications, best practices should be followed throughout the SDLC. These include:

  1. Code Review – Have all code reviewed by a security expert before being released
  2. Scanning – Scan your application for vulnerabilities. This can be done manually or with the help of automated penetration testing tools.
  3. Secure Importing – Import only secure and trusted frameworks and libraries
  4. Enforce Security Configurations – Disable all features that are not needed, such as debug mode or remote debugging tools. Ensure your configuration is limited to what is required for the application’s functionality and nothing else
  5. Keep Your Application Up-to-Date – You should also ensure you keep your applications updated with patches so no vulnerabilities are used against them
  6. Input Validation – Ensure that the users’ input is validated before it is processed by any other components in your application to avoid attacks such as SQL injection, XSS, etc.
  7. Deny Unnecessary Services – If an application does not need a certain service, such as an FTP server, then disable it. This would lead to a reduction in the surface area that could be targeted.
  8. Restrict Access – Restrict access to files and directories that should not be accessed by unauthorised users. You can use file permissions or authentication schemes to do this

These are only a few of the most essential security measures that app creators should take while ensuring their applications are safe. Based on the nature of your software/application creatively adapt security measures and different approaches for its testing.

In conclusion…

DAST will prove to be quite beneficial when it comes to evaluating the security of your software/applications. While it cannot make up for a complete security assessment, it can always be used in conjunction with static code analysis to get a more accurate assessment. The best way to utilize DAST is by using a checklist to ensure all areas of your application are covered. Security should be taken into consideration during the entire SDLC, not just at the end when it’s too late. By following the proper security measures and guidelines, you can help reduce your risk of being hacked and maintain the safety of your data.