OWASP Web Security Testing Guide

Information Gathering

Information Gathering is the first phase of any security assessment, focused on collecting as much data about a target as possible before testing begins. This phase uses passive and active reconnaissance techniques to map the attack surface and identify potential weaknesses.

Configuration and Deployment Management

Configuration and Deployment Management testing examines how securely the application infrastructure is configured and maintained. Misconfigurations are among the most common vulnerabilities and often provide the easiest path for attackers to gain unauthorized access.

Identity Management

Identity Management testing evaluates how the application creates, manages, and controls user identities. Weaknesses in identity management can lead to unauthorized account creation, privilege escalation, and account takeover attacks.

Authentication Testing

Authentication Testing verifies how securely the application confirms user identities. Weak authentication mechanisms are among the most exploited vulnerabilities, enabling account takeover, credential theft, and unauthorized access to sensitive data.

Authorization Testing

Authorization Testing evaluates whether the application properly enforces access controls after a user has been authenticated. These tests check if users can access resources, perform actions, or view data that should be restricted to other roles or users.

Session Management Testing

Session Management Testing examines how the application creates, maintains, and destroys user sessions. Weak session management can lead to session hijacking, session fixation, and cross-site request forgery, allowing attackers to impersonate legitimate users.

Input Validation Testing

Input Validation Testing covers the broadest and most technically deep category of web security tests, examining how the application handles untrusted input across all attack vectors. From XSS and SQL injection to SSRF and template injection, these vulnerabilities arise when user input is processed without proper validation and sanitization.

Error Handling

Error Handling testing examines how the application responds when things go wrong. Improper error handling can leak sensitive information about the application's internal structure, technology stack, and database through detailed error messages and stack traces.

Cryptography

Cryptography testing evaluates how the application implements encryption, hashing, and secure communication protocols. Weak or misconfigured cryptography can expose sensitive data in transit and at rest, undermining the confidentiality that users and regulations demand.

Business Logic Testing

Business Logic Testing examines the application's workflow rules and business processes for flaws that allow attackers to manipulate intended functionality. Unlike technical vulnerabilities, logic flaws exploit legitimate features in unintended ways and are invisible to automated scanners.

Client-side Testing

Client-side Testing examines vulnerabilities that execute in the user's browser rather than on the server. This category covers DOM-based XSS, client-side injection, clickjacking, and issues with browser storage, WebSockets, and cross-origin resource sharing.

API Testing

API Testing evaluates the security of application programming interfaces including GraphQL, REST, SOAP, and WebSocket APIs. As APIs become the primary communication mechanism for modern applications, securing them is critical to preventing data breaches and unauthorized access.