attack-surface.md

Attack Surface Analysis for reactphp/reactphp

Attack Surface: Unvalidated Input in Network Handlers

• Description: ReactPHP applications handling network requests (HTTP, WebSocket, raw sockets) are vulnerable if they fail to validate and sanitize input received through ReactPHP's network components. This is a direct consequence of building network applications with ReactPHP without secure input handling practices.
• ReactPHP Contribution: ReactPHP provides the foundation for building network applications. Its asynchronous nature makes it efficient at handling network traffic, but it also necessitates careful input validation within the application logic built using ReactPHP's networking tools.
• Example: A ReactPHP HTTP server application uses React\Http\Message\Request to process incoming requests. If the application directly uses data from request->getQueryParams() or request->getParsedBody() in a database query without sanitization, it's vulnerable to injection attacks.
• Impact: Data breaches, unauthorized access, data manipulation, potentially remote code execution (e.g., SQL Injection, Command Injection if input is used in commands).
• Risk Severity: Critical
• Mitigation Strategies:
  • Strict Input Validation: Implement robust input validation on all data obtained from network requests handled by ReactPHP.
  • Context-Aware Sanitization/Encoding: Sanitize or encode input data based on its intended use (e.g., SQL parameterization for database queries, HTML encoding for output).
  • Secure Coding Practices: Follow secure coding guidelines specifically for asynchronous network applications built with event-driven frameworks like ReactPHP.

Attack Surface: Denial of Service (DoS) via Network Resource Exhaustion

• Description: Attackers can exploit the network handling capabilities of ReactPHP applications to launch Denial of Service attacks by overwhelming the server with excessive connection requests or data. This arises from the inherent nature of network applications and how ReactPHP manages resources.
• ReactPHP Contribution: While ReactPHP's non-blocking architecture is designed for concurrency, applications built with it are still susceptible to resource exhaustion if connection limits and request handling are not properly configured within the ReactPHP application.
• Example: An attacker floods a ReactPHP WebSocket server with numerous connection requests, exploiting the application's default behavior of accepting connections. If the application lacks connection limits or proper resource management for new connections, it can exhaust server memory and CPU, leading to DoS.
• Impact: Application unavailability, service disruption, inability to serve legitimate users.
• Risk Severity: High
• Mitigation Strategies:
  • Connection Limits: Implement connection limits within the ReactPHP application to restrict the number of concurrent connections, especially from single IP addresses.
  • Rate Limiting: Apply rate limiting to control the number of requests processed within a given timeframe, preventing request floods.
  • Resource Quotas: Set resource quotas (e.g., memory limits per connection) within the ReactPHP application to prevent individual connections from consuming excessive resources.
  • Proper Configuration: Carefully configure ReactPHP's server components (e.g., HTTP server, WebSocket server) with appropriate timeouts and resource limits.

Attack Surface: Protocol Vulnerabilities in ReactPHP's Networking Implementations

• Description: Vulnerabilities can exist within the protocol implementations (HTTP, WebSocket, TLS/SSL) provided by ReactPHP itself or its underlying dependencies. Exploiting these vulnerabilities is directly related to the security of ReactPHP's core networking components.
• ReactPHP Contribution: ReactPHP provides its own implementations or relies on specific libraries for handling network protocols. Bugs or security flaws in these implementations directly impact applications using ReactPHP's networking features.
• Example: A vulnerability in ReactPHP's HTTP parser could be exploited by sending a crafted HTTP request that causes the parser to crash or misbehave, leading to DoS or potentially other vulnerabilities. Similarly, vulnerabilities in the TLS implementation used by ReactPHP could compromise secure connections established by ReactPHP applications.
• Impact: Denial of Service, information disclosure, potentially remote code execution depending on the vulnerability.
• Risk Severity: High to Critical (depending on the specific vulnerability and protocol).
• Mitigation Strategies:
  • Regularly Update ReactPHP and Dependencies: Keep ReactPHP and all its dependencies updated to the latest versions to patch known security vulnerabilities in protocol implementations.
  • Monitor Security Advisories: Stay informed about security advisories and vulnerability reports related to ReactPHP and its networking components.
  • Use Secure Protocol Configurations: Configure protocols (especially TLS/SSL) with strong security settings and disable insecure features within the ReactPHP application.

Attack Surface: Command Injection via Process Execution (react/child-process)

• Description: When using react/child-process to execute external commands based on user-controlled input without proper sanitization, applications become critically vulnerable to command injection. This is a direct risk introduced by using ReactPHP's process management component insecurely.
• ReactPHP Contribution: ReactPHP's react/child-process component enables asynchronous execution of external processes. If this component is used to execute commands constructed with unsanitized user input, it creates a direct pathway for command injection attacks within ReactPHP applications.
• Example: A ReactPHP application uses react/child-process to execute a command that includes a filename provided by a user. If the filename is not properly sanitized before being used in the command, an attacker can inject malicious commands within the filename, leading to arbitrary command execution on the server.
• Impact: Remote code execution, full system compromise, data breaches, denial of service.
• Risk Severity: Critical
• Mitigation Strategies:
  • Avoid Shell Execution: Prefer direct execution of commands with arguments passed as separate parameters to react/child-process to bypass shell interpretation and injection risks.
  • Strict Input Sanitization: If shell execution is unavoidable or arguments are constructed from user input, rigorously sanitize and validate all user-provided data used in command arguments.
  • Principle of Least Privilege: Run child processes with the minimum necessary privileges to limit the impact of potential command injection.
  • Code Reviews: Conduct thorough code reviews specifically focusing on the usage of react/child-process to identify and eliminate command injection vulnerabilities.

Attack Surface: Path Traversal Vulnerabilities (react/filesystem)

• Description: Applications utilizing react/filesystem to access files based on user-controlled input without proper path validation are vulnerable to path traversal attacks. This vulnerability is directly related to the insecure use of ReactPHP's filesystem component.
• ReactPHP Contribution: ReactPHP's react/filesystem component provides asynchronous filesystem operations. If applications use this component to access files based on user-provided paths without adequate validation, they become susceptible to path traversal exploits.
• Example: A ReactPHP application allows users to download files by specifying a filename. If the application uses react/filesystem to read the file based on this user-provided filename without path sanitization, an attacker can provide paths like "../../../../etc/passwd" to access sensitive files outside the intended directory.
• Impact: Information disclosure, access to sensitive files, potential for further system compromise.
• Risk Severity: High to Critical (depending on the sensitivity of accessible files).
• Mitigation Strategies:
  • Strict Path Validation: Implement robust validation and sanitization of all user-provided file paths before using them with react/filesystem. Use allowlists of permitted directories and filenames.
  • Path Canonicalization: Canonicalize file paths to resolve symbolic links and relative paths before file access to prevent traversal attempts.
  • Principle of Least Privilege (Filesystem Access): Run the application with minimal filesystem permissions, limiting access only to necessary directories and files.
  • Chroot Environments: Consider using chroot environments to restrict the application's filesystem view, limiting the impact of path traversal vulnerabilities.