There’s No Such Thing as Too Much Testing. What’s DAST and How it Helps Improve Security

Testing is one of the most challenging parts of the Software Development Life Cycle. Modern web applications can provide significant growth for companies from any domain. But the complexity of such systems, the need to work via the Internet, and sensitive data they deal with make it mandatory. Variety of tests that software developers must perform to ensure security and performance doesn’t allow to carry them out in one sitting. From a customer's perspective, at a first sight, this may not seem like the most attractive part of the deal. The software product is almost done, and all you have to do is to lend a hand and it will be in your possession. Unfortunately, in case you decide to skip testing, your own application can turn from a business booster to its gravedigger. Therefore, if you don’t want to launch an insecure application that can harm your reputation in the market, all testing activities should be performed timely and to the fullest extent. Today, we’ll consider Dynamic Application Security Testing or DAST, one of the most widespread techniques that helps to ensure the safety of your application.

How DAST Helps to Ensure Application Security

To improve security, DAST allows simulating the behavior of an end-user with malicious intent. This approach implies that the application will be subject to multiple simultaneous attacks and is performed through the front-end. In a few words, the team can use a DAST scanner to simulate different types of hacker attacks (SQL injections, XSS, etc.) and check the results in a search for deviations from normal behavior. Just like a potential hacker, the QA team members don’t have access to the application’s source code or at least pretend that they don’t have it. Such an approach allows DAST testing to become closer to real-life scenarios where the person performing attacks cannot exploit a vulnerability caused by a particular line of code.

Unfortunately, there’s no need to be a highly qualified web development expert to endanger the security of a particular web application. Scripts allowing malefactors to perform attacks on websites can be found online and, with a certain degree of skill, almost any person can become a threat. Among the most widespread types of attack we can consider already mentioned SQL injections allowing hackers to get full control over your database and cross-site scripting (XSS) that implies the execution of attacker’s code on your website or web application to steal sensitive information. If you own, for example, an e-commerce website, and users trust you with their personal information such as credit card numbers, most probably, you don’t want it to leak to some third party. The worst part is that it may take some time before you realize that there was a successful attack and the security of your web application is compromised. In this scenario, damage control will require a lot of effort.

Read Also Why Software Testing Plays a Key Role in a High-Quality Software Product Development

Development process that includes DAST helps to eliminate the probability of described issues by continually searching for weak spots in a web application long before it’s ready to be deployed. The dev team will receive automated notifications in case security issues are detected, which will help to take necessary measures on time. To achieve maximum effect, DAST must be applied as early as possible. Experienced developers know well that the sooner you detect a bug, the cheaper it will be to fix it. Also, it’s essential to ensure that the DevOps team has access to all reports generated during the DAST use. Because of this reason, it can be a good idea to integrate them into the bug-tracking system the development team uses.

DAST Pros and Cons

As an application testing technique, DAST may look pretty attractive. It allows you to get rid of security issues without even touching the source code. But, as it always happens, as soon as you find something that seems perfect to you, flaws begin to show up. DAST is not an exception and if you want to improve the security of your application using this method, you must know both its strengths and weaknesses.

Let’s start with advantages:

• It doesn’t rely on a specific technology. DAST doesn’t care about the source code of the application. It only cares about how well specific applications counter security threats. Therefore, it can be applied to any app without significant effort;
• The probability of false detection of a security threat is pretty low. This feature helps to ensure that QA team members and developers won’t be distracted as much as in the case of using other tools;
• Instantly detects security vulnerabilities. When used properly, DAST can find potential vulnerabilities instantly which helps to eliminate them before any damage is done;
• Can find configuration problems as well. Besides improving the application security, DAST can also detect possible configuration errors that may not break the entire system, but still can have pretty unpleasant consequences.

Unfortunately, there’s always a fly in the ointment. No application testing tool is perfect and all of them have their drawbacks. That’s why DAST is not a silver bullet and can’t solve all your security problems. Instead of choosing it as your one and only tool, you must use it alongside other methodologies. Such an approach will help different testing approaches to offset each other's drawbacks.

Read Also Major Testing Methodologies Overview

Among the weak side of DAST, we can note the following ones:

• Scalability can become an issue. The efficiency of this application testing approach highly depends on the expertise of a QA team specialist who’s writing the tests;
• Lack of attention to code. This feature can be considered as both a strong and weak side. DAST is platform independent but it can’t show developers which exact code line causes a problem which can cause some frustration;
• Security scans are time-consuming. Applying this tool requires time. Depending on the complexity of a web application, a full scan cycle can take up to a whole week.

Conclusions

Ensuring a web application security is a multi-step process. Attackers are getting more and more sophisticated, which requires improving security measures and testing them without interruptions. On the other hand, you don’t have to be a security expert to become a threat to e-commerce website owners, for example. Unskilled individuals that use software written by somebody else to attack websites at some point become such a common phenomenon that a special term has been coined. “Script kiddies” despite the funny name, can become a pretty serious problem. As they say, tough times call for tough decisions and the more testing tools developers have, the better.