.NET XSS: Examples and Prevention

The post serves as a comprehensive guide to understanding and mitigating cross-site scripting (XSS) vulnerabilities in .NET applications. It emphasizes the importance of ongoing security measures, highlighting that XSS is a common threat that can affect any programming language, including .NET. The post provides a basic overview of XSS, explaining it as an injection attack where malicious scripts are executed by exploiting user input mechanisms. It details the potential dangers of XSS, such as unauthorized data access and account theft, and demonstrates how .NET applications can be prone to XSS if not properly protected. Through practical examples using Visual Studio and ASP.NET Core, the post shows how to create a sample application and introduces methods to prevent XSS by encoding HTML tags to prevent execution. It also illustrates how vulnerabilities can be intentionally introduced and resolved, reinforcing best practices like not trusting user input and preferring safer data formats such as markdown. The article concludes by emphasizing the simplicity of avoiding XSS threats with proper precautions and encoding techniques.