.NET Content Security Policy Guide: What It Is and How to Enable It

Content Security Policy (CSP) is an essential security mechanism that helps mitigate web vulnerabilities like cross-site scripting and injection attacks by enforcing a set of directives that dictate which resources a browser can load on a webpage. The article explains how developers, particularly those using .NET, can implement CSP by adding specific policies to the server's response headers, thereby allowing only trusted resources to be executed. It outlines the practical steps to enable CSP, the potential issues developers might encounter, and how to address these through a "report-only" mode, which helps identify violations without enforcing the policy immediately. The article also suggests methods for handling in-line code violations, such as moving code to external files or using SHA hashes. The importance of ensuring content security is emphasized as part of building robust web applications, and the piece highlights the role of CSP in safeguarding user data and platform integrity. Written by Juan Reyes, the article draws on his diverse experiences and aims to provide valuable insights for developers looking to enhance their applications' security.