Skip to content

Latest commit

 

History

History
493 lines (465 loc) · 26 KB

sec-design.md

File metadata and controls

493 lines (465 loc) · 26 KB

BUSINESS POSTURE

  • Business Priorities and Goals:

    • Primary goal: To provide users with a comprehensive platform for managing their personal finances.
    • Key priorities:
      • User data security and privacy.
      • Accuracy and reliability of financial data.
      • User experience and ease of use.
      • Scalability to accommodate a growing user base.
      • Compliance with relevant financial regulations and data protection laws.

  • Business Risks:

    • Data breaches leading to exposure of sensitive financial and personal information, resulting in financial loss and reputational damage.
    • Financial fraud due to vulnerabilities in the application logic or security controls, leading to user losses and legal liabilities.
    • Regulatory non-compliance resulting in fines and legal repercussions.
    • Service unavailability impacting user trust and business continuity.
    • Loss of user trust and adoption due to security incidents or perceived lack of security.

SECURITY POSTURE

  • Existing Security Controls:

    • security control: Secure Software Development Lifecycle (SSDLC) - Assumed to be in place, but details are not provided in the input. Location: Not specified.
    • security control: Access Control - User authentication and authorization mechanisms are expected to be implemented to protect user data. Location: Application code.
    • security control: Input Validation - Input validation is expected to be implemented to prevent common web application vulnerabilities like SQL injection and cross-site scripting (XSS). Location: Application code, API endpoints.
    • security control: Encryption in Transit (HTTPS) - Expected to be enforced for all communication between users and the application. Location: Web server configuration, CDN.
    • security control: Regular Security Audits and Penetration Testing - Assumed to be conducted periodically to identify and remediate vulnerabilities. Location: Not specified, but part of security operations.
    • security control: Dependency Management - Utilizing dependency management tools to track and update software dependencies, mitigating risks from known vulnerabilities. Location: Build process, development environment.
    • security control: Code Reviews - Implementation of code review processes to identify potential security flaws before code deployment. Location: Development process.
    • accepted risk: Reliance on third-party services - The application likely integrates with third-party financial institutions and services, inheriting their security posture and potential vulnerabilities. Location: Third-party integrations.
    • accepted risk: Cloud Provider Security - Assuming cloud deployment, the application relies on the security controls provided by the cloud provider. Location: Cloud infrastructure provider.

  • Recommended Security Controls:

    • security control: Implement a Web Application Firewall (WAF) to protect against common web attacks. Location: In front of the application servers, CDN.
    • security control: Implement a robust Security Information and Event Management (SIEM) system for monitoring and alerting on security events. Location: Security operations infrastructure.
    • security control: Conduct regular vulnerability scanning and penetration testing, both automated and manual. Location: Security operations, DevSecOps pipeline.
    • security control: Implement static and dynamic application security testing (SAST/DAST) tools in the CI/CD pipeline. Location: CI/CD pipeline.
    • security control: Implement rate limiting and API security best practices to protect against abuse and denial-of-service attacks. Location: API Gateway, application code.
    • security control: Implement database encryption at rest to protect sensitive data stored in the database. Location: Database server configuration.

  • Security Requirements:

    • Authentication:
      • Requirement: Secure user authentication mechanism to verify user identity.
      • Requirement: Multi-factor authentication (MFA) should be offered to enhance account security.
      • Requirement: Password policy enforcement (complexity, rotation, etc.).
      • Requirement: Protection against brute-force attacks on authentication endpoints.
    • Authorization:
      • Requirement: Role-based access control (RBAC) to manage user permissions and access to resources.
      • Requirement: Principle of least privilege should be applied to all user and system accounts.
      • Requirement: Secure API authorization to ensure only authorized users and applications can access API endpoints.
    • Input Validation:
      • Requirement: Comprehensive input validation on all user inputs to prevent injection attacks (SQL injection, XSS, etc.).
      • Requirement: Input sanitization and encoding to neutralize malicious input.
      • Requirement: Validation should be performed both on the client-side and server-side.
    • Cryptography:
      • Requirement: Encryption of sensitive data at rest and in transit.
      • Requirement: Use of strong and up-to-date cryptographic algorithms and protocols.
      • Requirement: Secure key management practices for encryption keys.
      • Requirement: Hashing of passwords using strong one-way hashing algorithms with salt.

DESIGN

C4 CONTEXT

flowchart LR
    subgraph "Personal Finance Management System"
        A["Personal Finance Management System"]
    end
    B["User"] -- Uses --> A
    C["Bank APIs"] -- Integrates with --> A
    D["Investment APIs"] -- Integrates with --> A
    E["Email Service"] -- Sends notifications to --> A
    F["Analytics Platform"] -- Sends data to --> A
    style A fill:#f9f,stroke:#333,stroke-width:2px
Loading
  • Context Diagram Elements:
      • Name: Personal Finance Management System
      • Type: Software System
      • Description: The core application that provides personal finance management features to users.
      • Responsibilities:
        • User account management.
        • Financial data aggregation and processing.
        • Budgeting and spending tracking.
        • Financial planning and reporting.
        • Secure storage and retrieval of user data.
      • Security controls:
        • Authentication and authorization.
        • Input validation.
        • Data encryption at rest and in transit.
        • Security logging and monitoring.
      • Name: User
      • Type: Person
      • Description: Individual users who utilize the personal finance management system to manage their finances.
      • Responsibilities:
        • Provide accurate financial information.
        • Protect their account credentials.
        • Use the system responsibly and ethically.
      • Security controls:
        • Strong passwords.
        • Multi-factor authentication (optional, but recommended).
        • Awareness of phishing and social engineering attacks.
      • Name: Bank APIs
      • Type: External System
      • Description: APIs provided by various banks to access user's financial account information (transactions, balances, etc.).
      • Responsibilities:
        • Provide secure and reliable access to financial data.
        • Adhere to financial industry security standards.
        • Maintain data privacy and confidentiality.
      • Security controls:
        • API authentication and authorization (OAuth, API Keys).
        • Data encryption in transit (HTTPS).
        • Rate limiting and API security best practices.
      • Name: Investment APIs
      • Type: External System
      • Description: APIs provided by investment platforms to access user's investment account information (portfolio holdings, transactions, etc.).
      • Responsibilities:
        • Provide secure and reliable access to investment data.
        • Adhere to financial industry security standards.
        • Maintain data privacy and confidentiality.
      • Security controls:
        • API authentication and authorization (OAuth, API Keys).
        • Data encryption in transit (HTTPS).
        • Rate limiting and API security best practices.
      • Name: Email Service
      • Type: External System
      • Description: Third-party email service used to send notifications to users (e.g., account alerts, reports, marketing emails).
      • Responsibilities:
        • Reliable email delivery.
        • Secure handling of email addresses.
        • Compliance with email marketing regulations (e.g., GDPR, CAN-SPAM).
      • Security controls:
        • SPF, DKIM, and DMARC email authentication.
        • Data encryption in transit (TLS).
        • Compliance with data privacy regulations.
      • Name: Analytics Platform
      • Type: External System
      • Description: Third-party analytics platform used to collect and analyze application usage data for performance monitoring and business intelligence.
      • Responsibilities:
        • Secure collection and storage of analytics data.
        • Data anonymization and aggregation to protect user privacy.
        • Compliance with data privacy regulations.
      • Security controls:
        • Data encryption in transit (HTTPS).
        • Data anonymization and pseudonymization.
        • Access control to analytics data.

C4 CONTAINER

flowchart LR
    subgraph "Personal Finance Management System"
        A["Web Application" <br> Type: SPA <br> Technology: React/Next.js]
        B["API Gateway" <br> Type: Gateway <br> Technology: Nginx/Cloud Gateway]
        C["Backend API" <br> Type: Application <br> Technology: Node.js/Python]
        D["Database" <br> Type: Database <br> Technology: PostgreSQL/PlanetScale]
        E["Job Queue" <br> Type: Queue <br> Technology: Redis/RabbitMQ]
        F["Background Worker" <br> Type: Application <br> Technology: Node.js/Python]
    end
    G["User Browser"] -- Uses --> A
    A -- Calls API --> B
    B -- Routes to --> C
    C -- Reads/Writes --> D
    C -- Enqueues Jobs --> E
    F -- Dequeues Jobs --> E
    F -- Calls --> C
    H["Bank APIs"] -- Integrates with --> C
    I["Investment APIs"] -- Integrates with --> C
    J["Email Service"] -- Sends notifications via --> C
    K["Analytics Platform"] -- Receives data from --> C
    style A fill:#f9f,stroke:#333,stroke-width:2px
    style B fill:#f9f,stroke:#333,stroke-width:2px
    style C fill:#f9f,stroke:#333,stroke-width:2px
    style D fill:#f9f,stroke:#333,stroke-width:2px
    style E fill:#f9f,stroke:#333,stroke-width:2px
    style F fill:#f9f,stroke:#333,stroke-width:2px
Loading
  • Container Diagram Elements:
      • Name: Web Application
      • Type: Single Page Application (SPA)
      • Description: Frontend application built using React/Next.js, served to user browsers. Provides user interface for interacting with the personal finance management system.
      • Responsibilities:
        • User interface rendering and interaction.
        • Client-side input validation and data formatting.
        • Communication with the Backend API via API Gateway.
        • User session management (client-side).
      • Security controls:
        • Client-side input validation.
        • Protection against XSS vulnerabilities.
        • Secure handling of user sessions (cookies, tokens).
        • HTTPS communication.
      • Name: API Gateway
      • Type: Gateway
      • Description: Entry point for all API requests from the Web Application. Routes requests to the Backend API and handles cross-cutting concerns like authentication, authorization, rate limiting, and logging. Could be implemented using Nginx or a cloud-managed API Gateway service.
      • Responsibilities:
        • Request routing and load balancing.
        • API authentication and authorization.
        • Rate limiting and traffic management.
        • API request and response logging.
        • SSL termination.
      • Security controls:
        • API authentication and authorization mechanisms (e.g., JWT validation).
        • Rate limiting and DDoS protection.
        • WAF (Web Application Firewall) integration.
        • Security logging and monitoring.
      • Name: Backend API
      • Type: Application
      • Description: Backend application built using Node.js or Python, responsible for business logic, data processing, and integration with external systems. Exposes RESTful APIs consumed by the Web Application and Background Worker.
      • Responsibilities:
        • User authentication and authorization.
        • Business logic implementation for financial management features.
        • Data validation and processing.
        • Database interactions.
        • Integration with Bank APIs and Investment APIs.
        • Enqueueing background jobs.
        • Sending notifications via Email Service.
        • Sending data to Analytics Platform.
      • Security controls:
        • Server-side input validation.
        • Authorization checks for all API endpoints.
        • Secure database access and data handling.
        • Secure integration with external APIs (authentication, authorization, data encryption).
        • Security logging and monitoring.
      • Name: Database
      • Type: Database
      • Description: Persistent storage for application data, likely a relational database like PostgreSQL or a cloud-managed database service like PlanetScale. Stores user data, financial transactions, budgets, and other application data.
      • Responsibilities:
        • Data persistence and retrieval.
        • Data integrity and consistency.
        • Data backup and recovery.
        • Performance and scalability.
      • Security controls:
        • Database access control and authentication.
        • Data encryption at rest and in transit.
        • Regular database backups.
        • Database security hardening.
        • Monitoring and auditing of database access.
      • Name: Job Queue
      • Type: Queue
      • Description: Message queue system like Redis or RabbitMQ used for asynchronous task processing. Decouples long-running or resource-intensive tasks from the main API request-response cycle.
      • Responsibilities:
        • Reliable message queuing and delivery.
        • Task scheduling and prioritization.
        • Scalability and fault tolerance.
      • Security controls:
        • Access control to the queue system.
        • Message encryption (if sensitive data is queued).
        • Monitoring of queue health and performance.
      • Name: Background Worker
      • Type: Application
      • Description: Application that processes tasks from the Job Queue. Performs background tasks such as data aggregation, report generation, and integration with external APIs.
      • Responsibilities:
        • Processing tasks from the Job Queue.
        • Performing data aggregation and processing.
        • Generating reports.
        • Interacting with the Backend API and external systems.
      • Security controls:
        • Secure retrieval of tasks from the Job Queue.
        • Secure processing of tasks and data.
        • Logging and monitoring of background task execution.
        • Proper error handling and retries.

DEPLOYMENT

  • Deployment Options:

    • Option 1: Cloud-based deployment using a major cloud provider (AWS, GCP, Azure) leveraging managed services.
    • Option 2: Hybrid deployment, potentially using a mix of cloud and on-premises infrastructure (less likely for a startup).
    • Option 3: Fully on-premises deployment (least likely for a modern SaaS application).

  • Selected Deployment Architecture: Cloud-based deployment (Option 1) using AWS.

flowchart LR
    subgraph "AWS Cloud Environment"
        subgraph "Region"
            subgraph "Availability Zone 1"
                A["Web Application Instances" <br> Type: EC2/Fargate <br> Container: Web Application Container]
            end
            subgraph "Availability Zone 2"
                B["API Gateway" <br> Type: AWS API Gateway <br> Service: API Gateway]
                C["Backend API Instances" <br> Type: EC2/Fargate <br> Container: Backend API Container]
                D["Background Worker Instances" <br> Type: EC2/Fargate <br> Container: Background Worker Container]
            end
            subgraph "Availability Zone 3"
                E["Database Cluster" <br> Type: AWS RDS/PlanetScale <br> Service: Managed Database]
                F["Job Queue Service" <br> Type: AWS SQS/Redis ElastiCache <br> Service: Managed Queue]
            end
            B -- Routes to --> C
            A -- Accesses --> B
            C -- Accesses --> E
            C -- Enqueues Jobs --> F
            D -- Dequeues Jobs --> F
            D -- Calls --> C
        end
        G["User Browser"] -- Accesses --> B
        H["Bank APIs"] -- Accesses --> C
        I["Investment APIs"] -- Accesses --> C
        J["Email Service"] -- Accesses --> C
        K["Analytics Platform"] -- Accesses --> C
    end
    style A fill:#f9f,stroke:#333,stroke-width:2px
    style B fill:#f9f,stroke:#333,stroke-width:2px
    style C fill:#f9f,stroke:#333,stroke-width:2px
    style D fill:#f9f,stroke:#333,stroke-width:2px
    style E fill:#f9f,stroke:#333,stroke-width:2px
    style F fill:#f9f,stroke:#333,stroke-width:2px
Loading
  • Deployment Diagram Elements:
      • Name: Web Application Instances
      • Type: Compute Instance (EC2/Fargate)
      • Description: Instances running the Web Application container, deployed across multiple Availability Zones for high availability. Could be EC2 instances or containerized using Fargate.
      • Responsibilities:
        • Serving the Web Application to users.
        • Handling user traffic and requests.
        • Auto-scaling to handle varying load.
      • Security controls:
        • Security groups to restrict inbound and outbound traffic.
        • Regular patching and updates of underlying OS and runtime.
        • Hardened OS configuration.
      • Name: API Gateway
      • Type: AWS API Gateway (Managed Service)
      • Description: AWS managed API Gateway service, providing routing, authentication, authorization, and other API management features.
      • Responsibilities:
        • API request routing and management.
        • Authentication and authorization enforcement.
        • Rate limiting and DDoS protection.
        • SSL termination.
      • Security controls:
        • AWS IAM roles and policies for access control.
        • WAF integration.
        • AWS Shield for DDoS protection.
        • Security logging and monitoring provided by AWS.
      • Name: Backend API Instances
      • Type: Compute Instance (EC2/Fargate)
      • Description: Instances running the Backend API container, deployed across multiple Availability Zones for high availability. Could be EC2 instances or containerized using Fargate.
      • Responsibilities:
        • Running the Backend API application.
        • Processing API requests from the API Gateway.
        • Interacting with the Database and Job Queue.
        • Integrating with external APIs.
      • Security controls:
        • Security groups to restrict inbound and outbound traffic.
        • Regular patching and updates of underlying OS and runtime.
        • Hardened OS configuration.
      • Name: Background Worker Instances
      • Type: Compute Instance (EC2/Fargate)
      • Description: Instances running the Background Worker container, deployed across multiple Availability Zones for high availability. Could be EC2 instances or containerized using Fargate.
      • Responsibilities:
        • Running the Background Worker application.
        • Processing jobs from the Job Queue.
        • Performing background tasks.
      • Security controls:
        • Security groups to restrict inbound and outbound traffic.
        • Regular patching and updates of underlying OS and runtime.
        • Hardened OS configuration.
      • Name: Database Cluster
      • Type: AWS RDS/PlanetScale (Managed Service)
      • Description: Managed database service, either AWS RDS or PlanetScale, providing a highly available and scalable database cluster.
      • Responsibilities:
        • Persistent data storage.
        • Database management and maintenance.
        • High availability and fault tolerance.
        • Automated backups and recovery.
      • Security controls:
        • Database access control and authentication provided by the managed service.
        • Data encryption at rest and in transit provided by the managed service.
        • Regular security patching and updates managed by the service provider.
      • Name: Job Queue Service
      • Type: AWS SQS/Redis ElastiCache (Managed Service)
      • Description: Managed message queue service, either AWS SQS or Redis ElastiCache, providing a reliable and scalable job queue.
      • Responsibilities:
        • Message queuing and delivery.
        • Queue management and scaling.
        • High availability and fault tolerance.
      • Security controls:
        • Access control to the queue service provided by the managed service.
        • Encryption of messages in transit (depending on service).
        • Security monitoring provided by the managed service.

BUILD

flowchart LR
    A["Developer"] -- Code Changes --> B["Version Control System (GitHub)"]
    B -- Triggers --> C["CI/CD Pipeline (GitHub Actions)"]
    subgraph "CI/CD Pipeline"
        D["Source Code Checkout"]
        E["Build Stage" <br> - Compile Code <br> - Run Unit Tests]
        F["Security Scans" <br> - SAST <br> - Dependency Check <br> - Linting]
        G["Containerization" <br> - Build Docker Images]
        H["Artifact Repository" <br> - Store Docker Images <br> - Store Build Artifacts"]
        I["Deployment Stage" <br> - Deploy to AWS Environment]
        D --> E --> F --> G --> H --> I
    end
    C -- Manages --> D
    H -- Provides Artifacts to --> I
    style C fill:#f9f,stroke:#333,stroke-width:2px
    style H fill:#f9f,stroke:#333,stroke-width:2px
Loading
  • Build Process Elements:
      • Name: Developer
      • Type: Person
      • Description: Software developers who write and modify the application code.
      • Responsibilities:
        • Writing secure and high-quality code.
        • Performing local testing and code reviews.
        • Committing code changes to the Version Control System.
      • Security controls:
        • Secure development practices training.
        • Code review process.
        • Local development environment security.
        • Access control to development resources.
      • Name: Version Control System (GitHub)
      • Type: Code Repository
      • Description: GitHub repository used for storing and managing the application source code.
      • Responsibilities:
        • Source code version control and history tracking.
        • Collaboration and code sharing among developers.
        • Triggering CI/CD pipeline on code changes.
      • Security controls:
        • Access control to the repository (authentication and authorization).
        • Branch protection policies.
        • Audit logging of repository activities.
        • Vulnerability scanning of repository dependencies (GitHub Dependabot).
      • Name: CI/CD Pipeline (GitHub Actions)
      • Type: Automation System
      • Description: GitHub Actions used to automate the build, test, security scan, and deployment processes.
      • Responsibilities:
        • Automated build and testing of code changes.
        • Running security scans (SAST, dependency checks, linting).
        • Containerization of applications (building Docker images).
        • Publishing build artifacts to the Artifact Repository.
        • Automated deployment to the AWS environment.
      • Security controls:
        • Secure configuration of CI/CD pipeline workflows.
        • Secrets management for sensitive credentials (API keys, passwords).
        • Isolation of build environments.
        • Security scanning tools integration (SAST, dependency check).
        • Audit logging of pipeline execution.
      • Name: Artifact Repository
      • Type: Storage System
      • Description: Repository for storing build artifacts, such as Docker images and application binaries. Could be GitHub Container Registry, AWS ECR, or other artifact repositories.
      • Responsibilities:
        • Secure storage of build artifacts.
        • Versioning and management of artifacts.
        • Access control to artifacts.
        • Distribution of artifacts to deployment environments.
      • Security controls:
        • Access control to the artifact repository (authentication and authorization).
        • Vulnerability scanning of stored artifacts (e.g., Docker image scanning).
        • Data encryption at rest for stored artifacts.

RISK ASSESSMENT

  • Critical Business Processes:

    • User registration and account management.
    • Financial data aggregation from bank and investment APIs.
    • Processing and storage of financial transactions and user data.
    • Budgeting and financial planning calculations.
    • Report generation and data visualization.
    • User authentication and authorization to access their financial data.

  • Data Sensitivity:

    • Highly Sensitive Data:
      • User Personally Identifiable Information (PII): Name, email address, contact information, etc.
      • Financial Account Credentials (encrypted): Bank login details, investment account credentials.
      • Financial Transaction Data: Transaction history, account balances, investment holdings, income, expenses.
      • Budgeting and Financial Planning Data: User's financial goals, budget settings, financial plans.
    • Sensitive Data:
      • Application Usage Data: User activity logs, feature usage, performance data.
    • Public Data:
      • Publicly available financial information (if any).

QUESTIONS & ASSUMPTIONS

  • BUSINESS POSTURE:

    • Question: What is the risk appetite of the company? Is it a startup with a higher risk tolerance or an established company with a more conservative approach?
    • Question: What are the specific regulatory compliance requirements for the target market (e.g., GDPR, CCPA, PCI DSS, regional financial regulations)?
    • Assumption: The primary business goal is user growth and market adoption, balanced with a strong emphasis on data security and user trust.

  • SECURITY POSTURE:

    • Question: What existing security policies and procedures are in place within the organization?
    • Question: What is the current level of security awareness and training among development and operations teams?
    • Assumption: A basic level of security awareness and standard web application security practices are assumed to be in place, but require further enhancement.

  • DESIGN:

    • Question: What specific technologies are chosen for the Backend API (Node.js, Python, framework)? Database (PostgreSQL, PlanetScale, other)? Job Queue (Redis, RabbitMQ, cloud service)?
    • Question: What is the expected scale and performance requirements for the application?
    • Assumption: A cloud-native, microservices-oriented architecture is assumed, leveraging managed cloud services for scalability and resilience.
    • Assumption: The application is designed to handle sensitive financial data and requires robust security controls at all layers.