Threat Model Analysis for gofiber/fiber

Threat: Route Bypass Vulnerability

Description: An attacker crafts malicious requests to exploit weaknesses in Fiber's routing mechanism. This allows them to circumvent intended access controls and reach unauthorized application endpoints. Exploitation could involve manipulating URL parameters, path traversal techniques within routes, or leveraging inconsistencies in route matching logic within Fiber.
Impact: Critical. Successful route bypass can lead to unauthorized access to sensitive data, execution of privileged functionalities, and potentially full application compromise.
Fiber Component Affected: fiber.Router, fiber.App.Add, route parameter parsing logic.
Risk Severity: Critical
Mitigation Strategies:
- Implement comprehensive testing of routing configurations, specifically focusing on edge cases, unusual inputs, and potential path traversal attempts within route definitions.
- Adopt simple and predictable routing patterns to minimize complexity and potential for errors.
- Keep Fiber framework updated to the latest version to benefit from bug fixes and security patches in the routing engine.
- Enforce strong authorization checks within route handlers, ensuring that access control is not solely reliant on the routing mechanism itself.

Threat: Static File Directory Traversal

Description: If the application uses Fiber's static file serving capabilities, an attacker can craft requests with path traversal sequences (e.g., ../, ..%2F) to access files located outside the designated static file directory. This allows unauthorized retrieval of sensitive application files, configuration files, or even server-side code.
Impact: High. Unauthorized access to sensitive files can lead to information disclosure, exposure of application secrets, and potentially enable further attacks or full system compromise.
Fiber Component Affected: fiber.Static middleware.
Risk Severity: High
Mitigation Strategies:
- Carefully configure the fiber.Static middleware, strictly defining the root directory for static files and ensuring it points only to the intended public assets directory.
- Avoid storing sensitive files within or directly accessible from the static file serving directory.
- Regularly review and audit the configuration of fiber.Static middleware.
- Consider using a dedicated Content Delivery Network (CDN) or a specialized web server for serving static files, which may offer more robust security controls than serving static files directly from the application server.

Threat: Denial of Service (DoS) via Routing or Parsing Complexity

Description: An attacker exploits potential inefficiencies or vulnerabilities in Fiber's routing algorithm or request parsing logic to cause a Denial of Service. This could involve sending a large number of requests with complex or ambiguous routes that consume excessive server resources during route matching, or crafting malformed requests that overwhelm Fiber's parsing capabilities.
Impact: High. Successful DoS attack renders the application unavailable to legitimate users, leading to service disruption, potential financial losses, and reputational damage.
Fiber Component Affected: fiber.Router, fiber.Context, request parsing mechanisms within Fiber.
Risk Severity: High
Mitigation Strategies:
- Implement rate limiting middleware (fiber/middleware/limiter) to restrict the number of requests from a single source, mitigating volumetric DoS attacks.
- Simplify routing configurations to reduce the complexity of route matching and minimize resource consumption during routing.
- Thoroughly test application performance under load, including scenarios with complex routing and potentially malformed requests, to identify and address performance bottlenecks in Fiber's routing or parsing.
- Utilize infrastructure-level DoS protection mechanisms such as firewalls, intrusion detection/prevention systems, and cloud-based DDoS mitigation services to filter malicious traffic before it reaches the Fiber application.