Secure Coding in C# and .NET (Udemy.com)

Secure Coding in C# and .NET: Build Safer Applications with OWASP, ASP.NET Core Security, DevSecOps, and AI-Assisted Development

Modern developers cannot afford to treat security as an afterthought. Whether you are building ASP.NET Core APIs, web applications, microservices, or cloud-hosted .NET systems, you need to understand how vulnerabilities happen, how attackers exploit weak code, and how to prevent common security mistakes before they reach production.

In this hands-on course, you will learn how to write secure C# and .NET code using practical techniques based on real application security risks, OWASP guidance, and modern developer workflows. You will work through secure coding practices for authentication, authorization, input validation, data protection, secret management, dependency security, logging, CI/CD pipelines, and AI-assisted development with GitHub Copilot.

This course is designed for C# and .NET developers who want to go beyond making applications work. You will learn how to make them safer, more resilient, and better prepared for real-world security expectations.

What makes this course different?

Most application security courses are broad and language-agnostic. This course focuses on the Microsoft .NET ecosystem. You will see how secure coding concepts apply directly to C#, ASP.NET Core, Entity Framework Core, Identity, JWT, OAuth, OpenID Connect, Azure Key Vault, GitHub Actions, Azure DevOps, Docker, and GitHub Copilot.

You will also learn how AI-generated code can introduce security risks and how to use tools like GitHub Copilot more responsibly during development and review.

What you will learn

You will learn how to:

• Apply secure coding principles in C# and .NET applications

• Understand OWASP Top 10 risks from a .NET developer’s perspective

• Secure ASP.NET Core APIs and web applications

• Implement safer authentication and authorization flows

• Protect applications from broken access control and privilege escalation

• Validate and sanitize user input to reduce injection and XSS risks

• Protect sensitive data using encryption, hashing, TLS, and secure storage

• Manage secrets safely in local development, GitHub, Azure, and CI/CD workflows

• Avoid common security mistakes in configuration and deployment

• Use dependency scanning and static analysis to detect vulnerabilities

• Review and harden AI-generated code from GitHub Copilot

• Build security into the software development lifecycle

Secure authentication and authorization

Authentication and authorization are two of the most common sources of serious application security failures. In this course, you will examine how to protect login flows, tokens, claims, roles, policies, and access rules in ASP.NET Core applications.

You will explore .NET Identity, JWT, OAuth, OpenID Connect, MFA concepts, role-based authorization, claims-based authorization, and practical ways to reduce broken access control vulnerabilities.

Input validation, injection prevention, and safer APIs

You will learn how insecure input handling can lead to SQL injection, command injection, cross-site scripting, insecure deserialization, excessive data exposure, and unsafe business logic. You will use .NET validation tools, custom validators, allowlists, model validation, secure patterns, and practical coding techniques to reduce these risks.

Secret management and data protection

You will learn how to prevent the leakage of credentials, keys, tokens, and connection strings. You will examine safer approaches using local user secrets, environment variables, GitHub secrets, Azure Key Vault, secure configuration practices, and least-privilege access.

You will also learn how to protect sensitive data at rest and in transit using .NET cryptography APIs, hashing, encryption, TLS, and secure logging practices that avoid exposing personally identifiable information.

Secure build and deployment workflows.

Security does not stop when the code compiles. You will learn how to strengthen your build and deployment process using GitHub Actions, Azure DevOps, Docker, dependency vulnerability checks, static code analysis, and secure CI/CD practices.

You will also examine common supply chain security risks and how to reduce exposure in modern .NET development workflows.

Secure AI-assisted development with GitHub Copilot

AI tools can help developers move faster, but faster code is not automatically safer code. This course shows you how to use GitHub Copilot and AI-assisted workflows with a security mindset.

You will learn how to review AI-generated code, identify risky suggestions, ask better security-focused prompts, and use Copilot to help find, explain, and fix vulnerabilities in C# and .NET applications.

Tools and technologies covered

• C# and .NET

• ASP.NET Core

• ASP.NET Core Identity

• Entity Framework Core

• JWT, OAuth, OpenID Connect, MFA concepts

• OWASP Top 10

• Azure Key Vault

• GitHub Copilot

• GitHub Actions

• Azure DevOps

• Docker

• Security Code Scan

• OWASP Dependency Check

• Secure configuration and secret management

Who this course is for

This course is for:

• C# developers who want to write more secure applications

• ASP.NET Core developers building APIs, MVC, Razor Pages, or Blazor applications

• Backend developers responsible for authentication, authorization, and sensitive data

• Software engineers preparing for secure coding expectations in professional teams

• DevOps and cloud engineers supporting secure .NET deployments

• Students and career changers who want secure coding knowledge as part of their developer portfolio

• Architects and team leads who want practical security awareness across the .NET SDLC

Prerequisites

You should have basic experience writing C# code and running .NET applications. You do not need to be a cybersecurity expert. This course is designed to help developers build practical application security skills using familiar .NET tools and workflows.

By the end of the course