What Is Application Security Testing?
Application security testing is a systematic process of evaluating the security aspects of a software application to identify potential vulnerabilities and weaknesses that could be exploited by malicious actors. This testing is essential for ensuring that the application's code, configuration, and infrastructure are resilient against cyber attacks.
Security testing has become an inseparable part of the software development lifecycle (SDLC). By conducting thorough security testing, organizations can mitigate the risks of data breaches, unauthorized access, and other security threats, safeguarding sensitive information and maintaining the trust of their users.
This is part of a series of articles about application security.
3 Approaches to Application Security Testing
Here are three primary application security testing approaches:
Black-Box Security Testing
Black-box security testing, also known as external testing, involves assessing the security of an application from an external perspective, without access to its internal code or architecture. Testers simulate real-world attack scenarios to identify vulnerabilities that could be exploited by external adversaries.
By emulating the behavior of potential attackers, black-box testing helps uncover security weaknesses that may not be apparent from an internal vantage point, providing valuable insights into the application's susceptibility to external threats.
White-Box Security Testing
White-box security testing, also known as internal testing, involves analyzing the application's internal code, architecture, and design to identify potential security vulnerabilities. Testers have full access to the application's source code and can conduct in-depth assessments of its security controls, authentication mechanisms, and data handling processes.
By scrutinizing the application's internal components, white-box testing uncovers vulnerabilities that may not be apparent through external assessments, allowing for targeted remediation of security weaknesses at the code level.
Gray-Box Security Testing
Gray-box security testing combines elements of both black-box and white-box testing, offering a balanced approach to assessing application security. In gray-box testing, testers have limited knowledge of the application's internal workings, allowing them to simulate attacks from a semi-internal perspective. This approach enables testers to gain a deeper understanding of the application's security posture while still maintaining an element of external assessment.
Types of Application Security Testing Solutions
Here are the common types of security solutions used to perform application security testing:
Static Application Security Testing (SAST)
Static application security testing, commonly referred to as SAST, involves analyzing the application's source code, configuration files, and dependencies to identify potential security vulnerabilities and coding errors.
SAST solutions use automated scanning techniques to examine the codebase for known security issues, coding best practices, and compliance with security standards. By conducting static code analysis, organizations can proactively detect and remediate security vulnerabilities early in the software development lifecycle, reducing the potential impact of security flaws in production environments.
Dynamic Application Security Testing (DAST)
Dynamic application security testing, known as DAST, focuses on evaluating the security of running applications by simulating real-world attack scenarios and identifying potential vulnerabilities from an external perspective.
DAST solutions interact with the application in a manner similar to that of a potential attacker, probing for security weaknesses related to input validation, authentication mechanisms, and session management. By conducting dynamic testing, organizations can gain insights into the application's runtime behavior and identify vulnerabilities that may not be apparent through static code analysis alone.
Learn more in our detailed guide to DAST tools.
Interactive Application Security Testing (IAST)
Interactive application security testing, or IAST, represents a hybrid approach that combines elements of SAST and DAST to provide real-time security analysis during the application's runtime.
IAST solutions instrument the application to monitor its behavior and interactions with the underlying infrastructure, identifying security vulnerabilities and data flow anomalies as they occur. By offering continuous security assessment capabilities, IAST makes it possible to detect and address complex security issues in real time.
Vulnerability Scanning
Vulnerability scanners use various techniques to collect protocol headers of running services, including applications delivered over HTTP/HTTPS. Vulnerability scanners are either authenticated (have login access to the system) or unauthenticated (do not have login access to the system).
Strictly speaking, vulnerability scanners are not considered testing, because they are limited to identifying common vulnerabilities and exposures (CVEs) issues based on the version of runtime code. However, they are commonly used as part of a holistic application security testing program.
Software Composition Analysis (SCA)
Software Composition Analysis (SCA) is a process that allows security analysts to identify and manage open-source components within a software project. The primary objective of SCA is to manage security risks associated with open-source components.
SCA enables organizations to keep track of the open-source components used in their applications, thereby helping them identify any known vulnerabilities in these components. By using SCA, organizations can also ensure that they are in compliance with the licenses of the open-source components they use.
Runtime Application Self-Protection (RASP)
Runtime Application Self-Protection (RASP) works by embedding itself within an application or its runtime environment, thus allowing it to control the execution of the application.
RASP solutions can detect attacks in real-time by analyzing both the application's behavior and the context of that behavior. If an attack is detected, RASP can take action to prevent the attack, such as terminating the user session or alerting the security team.
Mobile Application Security Testing (MAST)
Mobile Application Security Testing (MAST) focuses on identifying vulnerabilities in mobile applications. Given the widespread use of mobile applications today, MAST has become increasingly important.
MAST involves testing mobile applications for potential security vulnerabilities. This includes testing the application's code, its interaction with other applications, and how it handles data. By conducting MAST, organizations can ensure that their mobile applications are secure and that they are not exposing sensitive data to potential threats.