Category Security

Implement ASP.NET Core OpenID Connect OAuth PAR client with Keycloak using .NET Aspire

This post shows how to implement an ASP.NET Core application which uses OpenID Connect and OAuth PAR for authentication. The client application uses Keycloak as the identity provider. The Keycloak application is hosted in a docker container. The applications are run locally using .NET Aspire. This makes it really easy to develop using containers. Code: […]

Add a Swagger UI using a .NET 9 Json OpenAPI file

This post shows how to implement a Swagger UI using a .NET 9 produced OpenAPI file. The Swagger UI is deployed to a secure or development environment and is not deployed to a public production target. Sometimes, it is required to deploy the Swagger UI to a development deployment target and not the test or […]

Sonar Webinar, end to end security of a web application

I did a Webinar on application security with Denis Troller and Sonar. I would like to thank Sonar for this opportunity, I really enjoyed it and found doing this together with you really professional, pleasant and fun to do. Here’s the recording: Link to the Sonar Q&A: https://community.sonarsource.com/t/webinar-end-to-end-security-in-a-web-application/115405 Link to the repository: https://github.com/damienbod/EndToEndSecurity

BFF secured ASP.NET Core application using downstream API and an OAuth client credentials JWT

This article shows how to implement a web application using backend for frontend security architecture for authentication and consumes data from a downstream API protected using a JWT access token which can only be accessed using an app-to-app access token. The access token is acquired using the OAuth2 client credentials flow and the API does […]

Migrate ASP.NET Core Blazor Server to Blazor Web

This article shows how to migrate a Blazor server application to a Blazor Web application. The migration used the ASP.NET Core migration documentation, but this was not complete and a few extra steps were required. The starting point was a Blazor Server application secured using OpenID Connect for authentication. The target system is a Blazor […]

Securing a Blazor Server application using OpenID Connect and security headers

This article shows how to secure a Blazor Server application. The application implements an OpenID Connect confidential client with PKCE using .NET 8 and configures the security headers as best possible for the Blazor Server application. OpenIddict is used to implement the identity provider and the OpenID Connect server. Code: https://github.com/damienbod/BlazorServerOidc OpenID Connect flow In […]

Securing a MudBlazor UI web application using security headers and Microsoft Entra ID

This article shows how a Blazor application can be implemented in a secure way using MudBlazor UI components and Microsoft Entra ID as an identity provider. The MudBlazor UI components adds some inline styles and requires a specific CSP setup due to this and the Blazor WASM script requirements. Code: https://github.com/damienbod/MicrosoftEntraIDMudBlazor Setup The application is […]

Authentication with multiple identity providers in ASP.NET Core

This article shows how to implement authentication in ASP.NET Core using multiple identity providers or secure token servers. When using multiple identity providers, the authentication flows need to be separated per scheme for the sign-in flow and the sign-out flow. The claims are different and would require mapping logic depending on the authorization logic of […]

Fix missing tokens when using downstream APIs and Microsoft Identity in ASP.NET Core

This article shows how a secure ASP.NET Core application can use Microsoft Entra ID downstream APIs and an in-memory cache. When using in-memory cache and after restarting an application, the tokens are missing for a value session stored in the cookie. The application needs to recover. Code: https://github.com/damienbod/bff-aspnetcore-angular OpenID Connect client setup The ASP.NET Core […]

Issue and verify BBS+ verifiable credentials using ASP.NET Core and trinsic.id

This article shows how to implement identity verification in a solution using ASP.NET Core and trinsic.id, built using an id-tech solution based on self sovereign identity principals. The credential issuer uses OpenID Connect to authenticate, implemented using Microsoft Entra ID. The edge or web wallet authenticates using trinsic.id based on a single factor email code. […]