threat-modeling.md

Threat Model Analysis for shakacode/react_on_rails

Threat: SSR Input Manipulation

• Threat: SSR Input Manipulation

  • Description: An attacker crafts malicious input (e.g., URL parameters, request headers, manipulated initial props, or data from a compromised database) that is passed to react_on_rails's server-side rendering process. This input exploits vulnerabilities in how the gem handles data before passing it to React's renderToString or renderToStaticMarkup, leading to server-side XSS-like vulnerabilities or other unintended code execution on the server. The attacker aims to inject JavaScript or manipulate the HTML structure before it reaches the client.
  • Impact:
    • Exposure of sensitive data included in the server-rendered HTML.
    • Execution of arbitrary JavaScript code in the context of the server-rendered page (potentially leading to further attacks, including server compromise).
    • Defacement of the website.
    • Redirection to malicious websites.
  • Affected Component: react_component helper (Rails side), Server-Side Rendering engine (Node.js side, specifically interacting with react-dom/server through react_on_rails's API), and the React component being rendered. The vulnerability lies in how react_on_rails bridges Rails data to the Node.js SSR environment.
  • Risk Severity: Critical
  • Mitigation Strategies:
    • Strict Input Validation (Rails): Before passing any data to react_component, rigorously validate and sanitize it on the Rails side. Use strong typing, whitelisting, and regular expressions. This is the primary defense, as it prevents malicious data from ever reaching the SSR process.
    • Contextual Encoding (Rails): Use Rails' built-in HTML escaping helpers (e.g., h, sanitize) to properly encode data within the rendered HTML, even on the server-side. This mitigates the risk of injected HTML tags.
    • Input Validation (React): Implement input validation within the React component itself, even if the data is already validated on the Rails side. This provides defense-in-depth.
    • Limit SSR Scope: Only use SSR for data that absolutely requires it. Prefer client-side rendering for highly dynamic or user-controlled content.
    • Avoid dangerouslySetInnerHTML (React): Never use dangerouslySetInnerHTML with untrusted data in server-rendered components.

Threat: Client-Side Component Hijacking

• Threat: Client-Side Component Hijacking

  • Description: An attacker injects a malicious script that leverages react_on_rails's client-side component registration mechanism (ReactOnRails.register). The attacker registers a malicious component with the same name as a legitimate component. When react_on_rails attempts to render the component, it executes the attacker's malicious code instead.
  • Impact:
    • Execution of arbitrary JavaScript code in the user's browser.
    • Theft of user data (e.g., form inputs, cookies).
    • Defacement of the website.
    • Redirection to malicious websites.
  • Affected Component: ReactOnRails.register (client-side), the global component registry maintained by react_on_rails. The vulnerability is in the lack of built-in protection against overriding existing component registrations.
  • Risk Severity: High
  • Mitigation Strategies:
    • Content Security Policy (CSP): Implement a strict CSP to prevent the execution of inline scripts and limit the sources from which scripts can be loaded. This is the most effective mitigation, as it prevents the initial script injection.
    • Subresource Integrity (SRI): Use SRI for all JavaScript files to ensure that the client only executes the exact code that was intended. This prevents attackers from modifying existing scripts.
    • Secure Build Process: Ensure your build process is secure and dependencies are vetted to prevent supply-chain attacks that could inject malicious code.
    • Code Reviews: Conduct thorough code reviews to identify and prevent potential vulnerabilities that could allow script injection.

Threat: SSR Data Exposure

• Threat: SSR Data Exposure

  • Description: Sensitive data is accidentally included in the props passed to a server-rendered component via the react_component helper. react_on_rails then serializes these props and includes them in the initial HTML, exposing the data in the page source.
  • Impact:
    • Exposure of sensitive user data.
    • Exposure of internal application secrets.
    • Potential for further attacks based on the leaked information.
    • Compliance violations.
  • Affected Component: react_component helper (Rails side), the mechanism by which react_on_rails passes props to the server-rendered React component.
  • Risk Severity: High
  • Mitigation Strategies:
    • Careful Prop Selection: Be extremely selective about what data is included in the props passed to react_component. Only include the absolute minimum necessary for the initial render.
    • Data Transformation (Rails): Transform data on the Rails side before passing it to react_component. Create a separate "view model" or DTO that contains only non-sensitive data. This is the most important mitigation.
    • API for Sensitive Data: For highly sensitive data, fetch it via an API call from the client-side after the initial render, rather than including it in the server-rendered HTML.
    • Code Reviews: Conduct thorough code reviews to ensure that sensitive data is not accidentally included in server-rendered props.

Threat: Vulnerability in Node.js or SSR Libraries used by react_on_rails

• Threat: Vulnerability in Node.js or SSR Libraries used by react_on_rails

  • Description: A vulnerability exists in the Node.js runtime, react-dom/server, or another dependency specifically used by react_on_rails for its SSR functionality. An attacker exploits this vulnerability to gain control of the server or execute arbitrary code through the SSR process initiated by react_on_rails.
  • Impact:
    • Complete server compromise.
    • Execution of arbitrary code on the server.
    • Data breaches.
    • Denial of service.
  • Affected Component: Node.js runtime, react-dom/server, any dependency of react_on_rails specifically involved in the SSR process. The vulnerability is not in react_on_rails itself, but in a component it uses.
  • Risk Severity: Critical
  • Mitigation Strategies:
    • Keep Node.js Updated: Regularly update your Node.js runtime to the latest stable version.
    • Dependency Auditing: Regularly audit your project's dependencies, paying special attention to those involved in SSR, for known vulnerabilities. Use npm audit or yarn audit.
    • Vulnerability Scanning: Use automated vulnerability scanning tools.
    • Least Privilege: Run the Node.js process (used by react_on_rails for SSR) with the least privileges necessary.
    • Security Advisories: Stay informed about security advisories related to Node.js, React, and react_on_rails.