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Dynamic application security testing (DAST) is a method of AppSec testing in which testers examine an application while it’s running, but have no knowledge of the application’s internal interactions or designs at the system level, and no access or visibility into the source program. This “black box” testing looks at an application from the outside in, examines its running state, and observes its responses to simulated attacks made by a testing tool. An application’s responses to these simulations help determine whether the application is vulnerable and could be susceptible to a real malicious attack.

How does DAST work?

DAST works by simulating automated attacks on an application, mimicking a malicious attacker. The goal is to find outcomes or results that were not expected and could therefore be used by attackers to compromise an application. Since DAST tools don’t have internal information about the application or the source code, they attack just as an external hacker would—with the same limited knowledge and information about the application. 

What problems does DAST solve?

Applications run the world economy and organizations are under tremendous pressure to stay ahead of the curve as our digital world accelerates. Businesses must continually innovate in an environment where sophisticated, relentless threat actors are ready to exploit any opportunity to disrupt, threaten critical data, and do damage. To successfully navigate this new world, it is vital to develop and execute a plan to ensure their applications are secure.

DAST works by simulating automated attacks on an application, mimicking a malicious attacker. The goal is to find outcomes or results that were not expected and could therefore be used by attackers to compromise an application. Since DAST tools don’t have internal information about the application or the source code, they attack just as an external threat actor would—with the same limited knowledge and information about the application. 




Using open source libraries helps DevOps teams build cloud applications faster, but it also puts organizations at risk of distributing security vulnerabilities that may be included as part of the open source code. Testing tools such as software composition analysis (SCA) enable DevOps teams to discover third-party and open source components that have been integrated into the applications. SCA solutions will typically scan these components looking for known common vulnerabilities and exposures (CVEs) and expired or missing software licenses and libraries that are out-of-date. Most open source libraries are composed of other open source libraries, creating a complex list of transitive dependencies. This hidden complexity can create security difficulties for DevOps teams. A modern security platform should include an SCA solution that can identify vulnerabilities in all the included libraries as well as the transitive dependencies that are embedded in the open source library. Security-conscious DevOps teams will often incorporate SCA scans into their continuous delivery (CD) process.

Once a DevOps team has built a running application, it needs to go through a series of black box tests prior to deployment to the cloud. These tests mimic the techniques that an attacker would use to find potential application security weaknesses. DAST solutions can find runtime vulnerabilities that are tough to spot through SCA, such as authentication and server configuration errors, code injection, SQL injection, and cross-site scripting errors. DAST tools use fault injection techniques on the application, such as inserting different malicious data into the software, to identify common security vulnerabilities. Because DAST scans look at running software, they occur further in the DevOps pipeline and may be run in a preproduction or production environment.

Why is DAST vital to application security?

As more businesses rely on web and mobile applications for success, application security vulnerabilities have rapidly become the most prevalent cause of data breaches. Thus, it is more important than ever for organizations to protect their applications and code.

  Challenges that organizations are currently facing

  • The shift to the cloud and cloud-native application technologies is making applications more complex.
  •  Massively distributed microservices and serverless functions mean that developers are focused solely on their own services, and no one has a complete grasp of the entire codebase.
  • As the sheer number of applications increases, the overall lines of software code deployed to the cloud expands the potential attack surface.
  • With more organizations focused on digital transformation, knowledge of the legacy code is waning as developers retire or change roles.
  • The prevalence of third-party and open source software make applications more composite in nature. As a result, a significant amount of the application code is developed outside the purview of the organization.
  • DevOps methodologies help development teams move faster but leave little time for manual or outdated security checks.

The velocity of code change is increasing, the underlying architecture where applications are hosted is changing, and the number of attacks against applications is growing. These three shifts capture the need for lightweight but comprehensive and highly usable application security solutions that serve the needs of both information security and application development teams working in concert. This is achieved by application security tools running efficiently, in the context of projects being worked on, reporting vulnerabilities and an application’s security state accurately. They must also support developer education by providing expert consultation for particularly difficult problems, and a solution that can be easily integrated into SDLCs.

Implementing DAST is not only necessary to determine the security posture of applications running in production and how they will likely interact with end users—it has now become essential for teams to keep up with the changing nature of applications and the knowledge of adversaries. Effective DevSecOps starts with taking feedback produced from DAST and integrating it into SecOps and DevOps tools. After all, DAST finds the actual vulnerabilities that put an organization and its end users at risk

  • Protect your applications and your code
  • Identify inherited and new vulnerabilities
  • Provide quality vulnerability assessment reports to expedite the remediation process

As organizations become increasingly dependent upon cloud platforms, they need to consider all aspects of security and not overlook the application security layer. With the continuing growth of new applications, APIs, and functionality, the application attack surface is rapidly expanding. This growth incents bad actors to use readily accessible tools and utilities to exploit applications with known vulnerabilities or susceptible code. Once an application is compromised, these bad actors can gain undetected access to confidential customer data, personally identifiable information, and/or other exploitable corporate assets, subjecting an organization to costly breaches of information and betrayal of customer trust.

Testing applications solely in development cannot protect them from being breached in production. A formal application security program is essential to reduce overall business risk. The right strategy and technology can identify the exploits that can be used in an attack on applications, and show how to protect application before a breach happens. When this is done correctly, organizations empower their teams to take responsibility and correct potential issues quickly, without disruption.

How are DAST and SAST different?


How can Synopsys help?

Unlike many DAST tools that slow security and development teams down with long lists of findings requiring lengthy triage to separate the real vulnerabilities from the false positives, WhiteHat™ Dynamic combines artificial intelligence (AI) with expert security analysis to give your teams the most accurate results in the shortest timeframe.

WhiteHat Dynamic delivers dynamic application security testing at the speed of DevOps and at enterprise scale. It rapidly and accurately finds vulnerabilities in websites and applications, with the scale and agility you need to identify security risks across your entire application portfolio.

  • Cloud-based. The SaaS delivery of WhiteHat Dynamic simplifies implementation, providing the agility to scale as fast as security testing needs evolve.
  • Continuous scanning. WhiteHat Dynamic supports continuous scanning that detects and adapts to code changes, ensuring that new functionality is automatically tested. This means that WhiteHat Dynamic keeps pace with the speed of your development processes and ensures that testing is consistently applied.
  • Accurate results. WhiteHat Dynamic utilizes AI-enabled verification that dramatically reduces false positives while minimizing vulnerability triage time, ensuring that developers are focused on the vulnerabilities with the highest risk.
  • Remediation guidance. WhiteHat Dynamic provides personalized remediation guidance from a team of application security experts, ensuring that identified vulnerabilities can be quickly and confidently addressed. This delivers a prioritized list of vulnerabilities and the guidance to fix them at business speed.
  • Risk scoring. The WhiteHat Dynamic Security Index provides a single score that enables you to gauge the overall status of web application security.
  • Headless operations. Many organizations have dashboards and other systems to manage application security testing. WhiteHat Dynamic supports these implementations by providing a rich set of APIs that enable tests to be scheduled and results to be captured programmatically. This ensures that WhiteHat Dynamic can be readily integrated into security and DevOps processes, and findings can be assimilated into organizational systems.

WhiteHat Dynamic has almost two decades of experience in the application security space and has developed a software-as-service (SaaS)-based modern security platform that detects security vulnerabilities in enterprise applications running both in the cloud and on-premises.

WhiteHat Dynamic was acquired by Synopsys, the recognized leader in software security and a Leader in the Gartner® Magic Quadrant™ for Application Security Testing (AST).

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