Okay, let's create a design document for the Duende Software repository, focusing on aspects relevant to threat modeling. I'll follow the structure you've outlined.
Duende Software provides commercial and open-source software, primarily focused on identity and access management (IAM). Their products, IdentityServer and BFF, are central to many organizations' authentication and authorization infrastructure.
Priorities and Goals:
- Provide robust and secure IAM solutions.
- Maintain a strong reputation for security and reliability.
- Support a wide range of industry standards (OAuth, OpenID Connect, etc.).
- Offer commercial products with support and additional features.
- Foster an active open-source community.
- Provide easy integration with .NET ecosystem.
Business Risks:
- Vulnerabilities in their software could lead to widespread security breaches in their customers' systems. This is the most critical risk.
- Reputational damage due to security incidents or perceived lack of security.
- Loss of customer trust and potential legal liabilities.
- Competition from other IAM providers.
- Failure to keep up with evolving security standards and threats.
- Supply chain attacks targeting their development or distribution processes.
Existing Security Controls (based on the GitHub repository and general knowledge of Duende's products):
- security control: Secure Development Practices: The repository structure, presence of documentation, and Duende's public statements suggest a commitment to secure development practices. This likely includes code reviews, security testing, and vulnerability management. Where: Described in public documentation and implied by the repository's content.
- security control: Adherence to Standards: Duende's products implement industry-standard protocols like OAuth 2.0 and OpenID Connect. This ensures interoperability and leverages the security reviews and scrutiny these standards receive. Where: Core functionality of IdentityServer and BFF.
- security control: Regular Updates: Duende provides regular updates and patches to address vulnerabilities and improve security. Where: Evidenced by release history and versioning.
- security control: Documentation: Comprehensive documentation helps users configure and deploy the software securely. Where: GitHub repository and Duende's website.
- security control: Community Engagement: An active open-source community can help identify and report security issues. Where: GitHub issues and discussions.
- security control: Use of HTTPS: The nature of the product implies that all communication should be secured using HTTPS. Where: Expected in all deployments.
- security control: Input Validation: Given the nature of the software, robust input validation is crucial to prevent injection attacks and other vulnerabilities. Where: Expected within the codebase of IdentityServer and BFF.
- security control: Authentication and Authorization: The core purpose of the software is to provide secure authentication and authorization mechanisms. Where: Core functionality of IdentityServer and BFF.
- security control: Cryptography: Secure use of cryptography for storing secrets, signing tokens, and encrypting communication. Where: Expected throughout the codebase.
- security control: Dependency Management: The project uses package managers (likely NuGet) to manage dependencies, which helps in tracking and updating third-party libraries. Where: Project files within the repository.
Accepted Risks:
- accepted risk: Complexity: IAM systems are inherently complex, increasing the risk of configuration errors and unforeseen vulnerabilities.
- accepted risk: Reliance on Third-Party Libraries: Like all software, Duende's products rely on third-party libraries, which may contain vulnerabilities.
- accepted risk: User Misconfiguration: The security of a deployment ultimately depends on the user configuring it correctly.
Recommended Security Controls:
- Implement a comprehensive Software Bill of Materials (SBOM) management system to track all dependencies and their vulnerabilities.
- Conduct regular penetration testing by independent security experts.
- Implement a bug bounty program to incentivize external security researchers to find and report vulnerabilities.
- Provide security hardening guides and checklists for users.
- Offer security training for developers and users.
Security Requirements:
- Authentication:
- Support for multi-factor authentication (MFA).
- Secure password storage using strong hashing algorithms.
- Protection against brute-force attacks.
- Account lockout mechanisms.
- Secure session management.
- Authorization:
- Fine-grained access control using roles and permissions.
- Support for standard authorization protocols (OAuth 2.0, OpenID Connect).
- Protection against privilege escalation attacks.
- Input Validation:
- Strict validation of all user inputs to prevent injection attacks (e.g., SQL injection, cross-site scripting).
- Use of allowlists rather than blocklists where possible.
- Cryptography:
- Use of strong, industry-standard cryptographic algorithms.
- Secure key management practices.
- Protection of sensitive data at rest and in transit.
- Regular review of cryptographic implementations.
graph LR
subgraph Duende Software Ecosystem
A[Duende IdentityServer/BFF]
end
B[Users] --> A
C[External Identity Providers] --> A
D[Client Applications] --> A
E[APIs] --> A
A --> E
A --> C
A --> D
Element Descriptions:
-
- Name: Duende IdentityServer/BFF
- Type: Software System
- Description: The core software system providing identity and access management services.
- Responsibilities:
- Authenticating users.
- Issuing and validating security tokens.
- Managing user sessions.
- Providing an API for client applications.
- Integrating with external identity providers.
- Security Controls: Authentication, Authorization, Input Validation, Cryptography, Secure Development Practices, Adherence to Standards, Regular Updates.
-
- Name: Users
- Type: Person
- Description: Individuals who interact with the system to access protected resources.
- Responsibilities:
- Providing credentials for authentication.
- Managing their accounts.
- Adhering to security policies.
- Security Controls: Strong passwords, Multi-Factor Authentication (MFA).
-
- Name: External Identity Providers
- Type: Software System
- Description: Third-party systems (e.g., Google, Facebook) that can be used for authentication.
- Responsibilities:
- Authenticating users.
- Providing user information to IdentityServer.
- Security Controls: Implemented by the external provider; IdentityServer should validate responses securely.
-
- Name: Client Applications
- Type: Software System
- Description: Applications that use IdentityServer/BFF to authenticate users and access protected resources.
- Responsibilities:
- Initiating authentication flows.
- Handling security tokens.
- Accessing APIs securely.
- Security Controls: Secure handling of tokens, HTTPS communication, Input Validation.
-
- Name: APIs
- Type: Software System
- Description: Protected resources that client applications access after authentication.
- Responsibilities:
- Providing data and services to authorized clients.
- Validating access tokens.
- Security Controls: Authorization, Input Validation, HTTPS communication.
graph LR
subgraph Duende IdentityServer/BFF
A[Web Application] --> B(Database)
A --> C[Token Service]
A --> D[User Management API]
A --> E[Configuration API]
end
F[Client Applications] --> A
G[External Identity Providers] --> A
Element Descriptions:
-
- Name: Web Application
- Type: Web Application
- Description: The main application that handles user requests and interacts with other components.
- Responsibilities:
- Handling user authentication requests.
- Rendering user interfaces.
- Managing user sessions.
- Communicating with other internal services.
- Security Controls: Input Validation, Authentication, Session Management, HTTPS.
-
- Name: Database
- Type: Database
- Description: Stores user data, client configuration, and other persistent information.
- Responsibilities:
- Storing and retrieving data securely.
- Enforcing data integrity.
- Security Controls: Access Control, Encryption at Rest, Auditing.
-
- Name: Token Service
- Type: Service
- Description: Responsible for issuing and validating security tokens.
- Responsibilities:
- Generating tokens based on successful authentication.
- Validating tokens presented by client applications.
- Managing token signing keys.
- Security Controls: Cryptography, Secure Key Management.
-
- Name: User Management API
- Type: API
- Description: Provides an interface for managing user accounts.
- Responsibilities:
- Creating, updating, and deleting user accounts.
- Managing user roles and permissions.
- Security Controls: Authentication, Authorization, Input Validation.
-
- Name: Configuration API
- Type: API
- Description: Provides an interface for configuring IdentityServer/BFF.
- Responsibilities:
- Managing client configurations.
- Configuring identity providers.
- Setting security policies.
- Security Controls: Authentication, Authorization, Input Validation.
-
- Name: Client Applications
- Type: Software System
- Description: Applications that use IdentityServer/BFF to authenticate users and access protected resources.
- Responsibilities:
- Initiating authentication flows.
- Handling security tokens.
- Accessing APIs securely.
- Security Controls: Secure handling of tokens, HTTPS communication, Input Validation.
-
- Name: External Identity Providers
- Type: Software System
- Description: Third-party systems (e.g., Google, Facebook) that can be used for authentication.
- Responsibilities:
- Authenticating users.
- Providing user information to IdentityServer.
- Security Controls: Implemented by the external provider; IdentityServer should validate responses securely.
Possible Deployment Solutions:
- Cloud-based (Azure, AWS, GCP): Using managed services like Azure App Service, AWS Elastic Beanstalk, or Google App Engine.
- Containerized (Docker, Kubernetes): Deploying the application as a container within a container orchestration platform.
- On-premises: Deploying directly to a Windows Server using IIS.
Chosen Solution (for detailed description): Containerized (Kubernetes)
graph LR
subgraph Kubernetes Cluster
subgraph Namespace
A[IdentityServer Pod] --> B[Database Pod]
A --> C[Ingress Controller]
end
end
D[Client Applications] --> C
E[External Identity Providers] --> C
Element Descriptions:
-
- Name: IdentityServer Pod
- Type: Container
- Description: A Kubernetes pod running the IdentityServer/BFF application.
- Responsibilities:
- Running the IdentityServer/BFF application.
- Handling incoming requests.
- Security Controls: Network Policies, Resource Limits, Security Context.
-
- Name: Database Pod
- Type: Container
- Description: A Kubernetes pod running the database (e.g., SQL Server, PostgreSQL).
- Responsibilities:
- Storing and retrieving data.
- Security Controls: Network Policies, Persistent Volume Claims with Encryption, Database-level Security.
-
- Name: Ingress Controller
- Type: Load Balancer
- Description: A Kubernetes Ingress controller that manages external access to the IdentityServer service.
- Responsibilities:
- Routing traffic to the IdentityServer pod.
- Terminating TLS connections.
- Security Controls: TLS Certificates, Network Policies.
-
- Name: Client Applications
- Type: External System
- Description: Applications accessing IdentityServer from outside the cluster.
- Responsibilities: N/A (external)
- Security Controls: N/A (external)
-
- Name: External Identity Providers
- Type: External System
- Description: External identity providers accessed by IdentityServer.
- Responsibilities: N/A (external)
- Security Controls: N/A (external)
The build process likely involves the following steps:
- Developer commits code to the GitHub repository.
- A Continuous Integration (CI) system (e.g., GitHub Actions, Azure DevOps) triggers a build.
- The CI system restores dependencies (using NuGet).
- The code is compiled.
- Static analysis tools (SAST) are run to identify potential security vulnerabilities.
- Unit and integration tests are executed.
- If all checks pass, a build artifact (e.g., a Docker image) is created.
- The artifact is pushed to a container registry (e.g., Docker Hub, Azure Container Registry).
graph LR
A[Developer] --> B[GitHub Repository]
B --> C[CI System (GitHub Actions)]
C --> D[Restore Dependencies (NuGet)]
D --> E[Compile Code]
E --> F[Static Analysis (SAST)]
F --> G[Run Tests]
G --> H[Create Artifact (Docker Image)]
H --> I[Container Registry]
Security Controls in Build Process:
- security control: CI/CD Pipeline: Automates the build and testing process, ensuring consistency and reducing the risk of manual errors.
- security control: SAST: Identifies potential vulnerabilities in the code before deployment.
- security control: Dependency Scanning: Checks for known vulnerabilities in third-party libraries.
- security control: Code Signing: Ensures the integrity and authenticity of the build artifacts.
- security control: Least Privilege: The CI/CD system should have only the necessary permissions to perform its tasks.
Critical Business Processes:
- User Authentication and Authorization: This is the core function of the system and must be protected at all costs.
- Token Issuance and Validation: The security of the entire system relies on the secure generation and validation of tokens.
- User Data Management: Protecting user data from unauthorized access and modification is crucial.
- System Configuration: Preventing unauthorized changes to the system's configuration is essential.
Data Sensitivity:
- User Credentials (passwords, MFA secrets): Highly sensitive.
- Personally Identifiable Information (PII): Sensitive, subject to privacy regulations (e.g., GDPR, CCPA).
- Security Tokens: Highly sensitive, as they grant access to protected resources.
- Client Configuration Data: Sensitive, as it could be used to impersonate clients.
- Audit Logs: Potentially sensitive, as they may contain information about user activity.
Questions:
- What specific SAST and DAST tools are used in the development process?
- What is the process for handling security vulnerabilities reported by external researchers?
- What are the specific procedures for key management and rotation?
- Are there any specific compliance requirements (e.g., FedRAMP, HIPAA) that need to be considered?
- What is the disaster recovery plan for the system?
- What kind of penetration tests are performed and how often?
Assumptions:
- BUSINESS POSTURE: Assumes that Duende Software prioritizes security and has a strong commitment to addressing vulnerabilities.
- SECURITY POSTURE: Assumes that secure coding practices are followed, even if not explicitly documented in the repository. Assumes regular security audits are conducted.
- DESIGN: Assumes a standard deployment model using Kubernetes, although other options are possible. Assumes the use of a CI/CD system for building and deploying the software.