Application Security Testing: DAST, SAST and IAST.

Tests are a crucial part of the software development life cycle (SDLC) and are used to ensure that the software is functioning as intended. There are various types of tests that can be performed, including functional and non-functional tests.

Functional testing is used to verify that the software meets its specified requirements. This type of testing checks the software’s functionality by testing each feature and ensuring that it behaves as expected.

Non-functional testing is a type of software testing that evaluates the performance, scalability, reliability, security and other non-functional aspects of a software application. It ensures that the system meets the requirements that are not related to specific functions or features, but rather to the overall quality of the product.

Security testing is a special type of non-functional testing that is focused on identifying vulnerabilities in the system that could be exploited by malicious actors. This includes testing for things like SQL injection and cross-site scripting (XSS).

Security testing is a key part of DevSecOps, which is a process that combines development, security, and operations to improve the overall security of the software. It covers the entire system and includes testing all areas that could be targeted by attackers.

Pre-reading Requirements

I assume readers have a basic understanding of the fundamentals of software engineering and cybersecurity.

Summary

• Application Security Testing (AST) is a critical process for analyzing the security of applications and systems, aimed at identifying potential vulnerabilities and threats. Its goal is to detect and mitigate security risks before they can be exploited, embodying the principle of "Shifting Security Left" in the development lifecycle.
• Dynamic Application Security Testing (DAST) evaluates application behavior during runtime, mimicking hacking techniques to dynamically probe the application. It assesses the application's responses to these attacks to determine susceptibility to various known threats.
• Static Application Security Testing (SAST), on the other hand, inspects the application's source code or binaries for vulnerabilities by analyzing its syntax, structure, procedures, and interfaces.
• Interactive Application Security Testing (IAST), a methodology proposed by Gartner, represents an innovative approach to uncovering security vulnerabilities in web applications. IAST employs a hybrid strategy, integrating aspects of both DAST and SAST, to monitor runtime functions and data flows in real time, thus providing a comprehensive analysis of security issues.

What is Application Security Testing?

Application Security Testing or AST is a process that involves analyzing the security of applications and systems by looking for potential vulnerabilities and threats. It is designed to detect and prevent potential security risks before they can be exploited (Shift Security Left).

AST Categories

There are three types of application security testing: black-box, gray-box, and white-box.

Black-box security testing is a type of testing where the tester does not have any knowledge of how the system works internally. This type of testing simulates an external attack and is used to test the application’s security from end to end. This includes testing security misconfigurations and integrations between systems. The main benefit of black-box testing is that it can identify security vulnerabilities that would be missed by other testing methods. However, it can also miss vulnerabilities in the underlying application.

Gray-box security testing is similar to black-box testing. However, in gray-box testing, the tester has some knowledge of the system or application, such as the architecture. This simulates the case of a privileged insider who uses their knowledge to conduct a more sophisticated attack. Gray-box testing is useful for identifying vulnerabilities that would be missed by black-box testing, but it is also more time-consuming and resource-intensive.

White-box security testing posits that the tester has complete knowledge of the system. This type of testing is typically done by an automated tool that scans software source code for security defects. A classic example of white-box testing is static application security testing (SAST). White-box testing is useful for identifying vulnerabilities in the underlying code, but it can also be resource-intensive and may not identify all vulnerabilities.