DAST and Other DevSecOps Best Practices

Ensuring source code security is a critical link in the software engineering chain. The good news is that there is no need to reinvent the wheel to do it. With specially crafted tools, it is easy to check applications for vulnerabilities throughout the development cycle. The current popularity of these automatic instruments stems from the growingly stringent regulatory guidelines and high standards on customers’ end.

This write-up will shed light on some variants of source code testing tools out there. It will zoom into the distinguishing characteristics of Dynamic, Static, and Interactive Application Security Testing (DAST, SAST, and IAST) solutions as well as the Runtime Application Self-Protection (RASP) technology. You will also learn what the future may hold for this booming market of highly effective security scanners.

Why check code for security loopholes?

Most companies are doing a good job closing security gaps inside their perimeter through timely patches of mainstream software such as operating systems and database management solutions. When it comes to protecting custom tools created for specific tasks, proactivity isn’t always the case. This could provide attackers with opportunities to infiltrate the enterprise infrastructure.

Therefore, organizations need to know what code fragments are being used in different parts of their IT environment while staying abreast of the corresponding authorship information. With such an inventory in place, security teams can quickly fix bugs identified in specific fragments, and where possible, assign this task to the author of the crude code.

Since all tiers of every company’s digital architecture overlap and depend on each other, it is important to beef up protection from the ground up. Meanwhile, setting clear-cut goals of the code assessment workflow can minimize the costs. The common objectives include regulatory compliance and forestalling data breaches as well as malware raids.

Code testing tools help software engineers avoid the costs of addressing flaws found after a system is released. From a corporate customer’s perspective, applying patches is a resource-intensive process, and therefore software auditing best practices can save a good deal of time and financial resources later on.

The profit model of an organization may directly hinge on specific electronic services and applications such as financial and trading solutions. In the aftermath of a serious cyber incursion such as ransomware against these sensitive systems, the business may encounter a deadly mix of both reputational and monetary losses.

Whereas checking code for vulnerabilities from the start is not the only component of DevSecOps, it is one of the critical building blocks of software development done right. Reliance on patches is a cat-and-mouse game that potentially gives threat actors time enough to execute an attack. A forward-thinking tactic should involve the “Shift Left” approach. It is geared toward finding and eliminating flaws early in the software development and delivery lifecycle.

The legal facet of the matter should not be underestimated either. Every company needs to keep a record of its proprietary code, know who will own it in a business split-up scenario, and stay on top of the licensing requirements of third-party components. Proper code auditing can help lawyers do their work when organizational changes kick in.

How effective are open-source scanners?

Free or cheap security is a misnomer to an extent. There are always pitfalls hidden in plain sight, such as limited functionality or monetization through ads. With that in mind, it might still be challenging to determine whether a commercial scanner is better than a free counterpart. When faced with this dilemma, you should ask yourself the following question: which tool is more suited to a specific task? Moreover, it is a good idea to use different scanners at different stages of the development cycle.

Open-source scanners deliver the essentials of code security. Still, they tend to be less effective than commercial alternatives when it comes to spotting complex vulnerabilities and getting actionable insights into the ways to address these non-mainstream imperfections. The recommendation functionality makes a difference because there is a big gap between simply being aware of a problem and knowing how to fix it. Some tools can even remediate flaws automatically.

It takes a lot of financial and human resources to equip a product with comprehensive vulnerability reviews along with relevant security recommendations and keep these features up to date. Most authors of free scanners cannot afford to deliver such functionality.

DAST technology fundamentals

The idea behind Dynamic Application Security Testing (DAST) is to probe an application for weaknesses while it is running. These tools mimic attacks from the outside to identify anomalous behaviors of the application that might stem from vulnerabilities in its exposed interfaces. DAST has no access to the source code, and therefore it follows a black-box testing logic.

While this mechanism cannot spot specific strings of shoddy code, it is incredibly effective in unveiling prevalent runtime issues such as cross-site scripting (XSS), server security misconfiguration, SQL injection, path traversal, and user authentication blunders.

One of the benefits of using DAST is its technology-neutral essence. Since it does not involve scrutinizing the source code, it is not bound by specific programming languages and can be applied to any software. Also, it simulates real-world compromise scenarios to the maximum and provides a hands-on view of the loopholes that attackers will most likely try to exploit down the line.

Other scanners in the DevSecOps ecosystem

Code testers can leverage several more types of tools to get the big picture. These include Static (SAST), Interactive (IAST), and Feedback-based Application Security Testing (FAST) instruments. A technology called RASP resembles DAST in that it detects and fends off attacks in real-time, except that it works as a sort of internal application firewall. Software Composition Analysis (SCA) tools form an extra layer of protection by assessing third-party components integrated into a system.

None of these instruments should be considered a replacement for another. Each one covers a certain area of the DevSecOps routine. For instance, SAST helps avoid security slip-ups when writing source code, whereas DAST and IAST determine the attack vectors the application is the most susceptible to.

Instead of treating static and dynamic analyzers as two extremes that don’t get along with each other, companies should combine them to harden their security. Many flaws can only be uncloaked in a static situation, some manifest themselves in dynamics, and quite a few are lost in between.

Common deployment roadblocks

Crude interoperability between information security experts and software engineers can hamper the smooth implementation of source code analysis tools. These teams may have different opinions about the severity of a coding flaw and the urgency of applying a patch.

Vulnerability databases may help reach a consensus, but with the caveat that they do not always fit the context of a specific development framework. Moreover, the threat models of different applications vary and should be taken into account when evaluating how critical a vulnerability is and prioritizing the fix. A good deal of these inconsistencies can be addressed by creating a list of security requirements at the early development stage.

It is also important for an organization’s security professionals to understand that an error and a vulnerability are not necessarily synonymous. When interacting with developers, they should provide a comprehensive summary of the identified problem with references to firmly established international practices.

Going forward

Application security scanners will most likely move to the cloud in the near future. This evolutionary shift is already taking place, with some providers generating up to 50 percent of their revenues via cloud-based security tools.

Regulatory requirements that pertain to code security are becoming more rigid. To tailor tools for major industries, developers have to think beyond purely functional criteria. That said, writing tamper-proof code is just as important as ensuring the stable operation of a digital infrastructure these days.