dotnet-api-security

API-level authentication, authorization, and security patterns for ASP.NET Core. This skill owns API auth implementation: ASP.NET Core Identity configuration, OAuth 2.0/OIDC integration, JWT bearer token handling, passkey (WebAuthn) authentication, CORS policies, Content Security Policy headers, and rate limiting.

Auth ownership: This skill owns API-level auth patterns. Blazor-specific auth UI (AuthorizeView, CascadingAuthenticationState, client-side token handling) -- see [skill:dotnet-blazor-auth] when it lands. OWASP security principles (cross-cutting vulnerability mitigations) -- see [skill:dotnet-security-owasp].

Out of scope: OWASP Top 10 mitigations and deprecated security patterns -- see [skill:dotnet-security-owasp]. Secrets management and secure configuration -- see [skill:dotnet-secrets-management]. Cryptographic algorithm selection -- see [skill:dotnet-cryptography]. Blazor auth UI components -- see [skill:dotnet-blazor-auth].

Cross-references: [skill:dotnet-security-owasp] for OWASP security principles, [skill:dotnet-secrets-management] for secrets handling, [skill:dotnet-cryptography] for cryptographic best practices.

ASP.NET Core Identity

ASP.NET Core Identity provides user management, password hashing, role-based authorization, and two-factor authentication out of the box. It is the recommended starting point for applications that manage their own user accounts.