4️⃣4 - Cross-Site Scripting (XSS)

Topics

XSS Anatomy
Reflected XSS
Stored XSS
DOM-Based XSS
Identifying & Exploiting XSS with XSSer

Cross Site Scripting (XSS) | OWASP Foundationowasp.org

Cross-Site Scripting (XSS)

Cross-Site Scripting (XSS) constitutes a client-side web vulnerability enabling attackers to embed malicious scripts into web pages.

This vulnerability often arises from inadequate input sanitization/validation within web applications.

Attackers exploit XSS vulnerabilities to insert harmful code into web applications. Given that XSS is a client-side vulnerability, these scripts execute within the victim's browser.

XSS vulnerabilities impact web applications deficient in input validation and reliant on client-side scripting languages such as JavaScript, Flash, CSS, etc.

Web Basics

14 - Hacking Web Apps

Practise

🔬 There are many vulnerable testing web apps like:

DVWA

The Damn Vulnerable Web Application (DVWA) is a web application built with PHP and MySQL intentionally designed to be susceptible to security vulnerabilities. Its primary purpose is to serve as a resource for security professionals to assess their skills and tools within a legal context. Additionally, it aids web developers in gaining a deeper understanding of the processes involved in securing web applications and facilitates learning about web application security for both students and teachers in a controlled classroom setting.

DVWA is designed to provide a platform for practicing various common web vulnerabilities at different difficulty levels, all presented through a simple and user-friendly interface. It's important to note that there are deliberate both documented and undocumented vulnerabilities within the software, encouraging users to explore and identify as many issues as possible.