attack-surface.md

Attack Surface Analysis for laravel/framework

Attack Surface: Mass Assignment Vulnerabilities

• Description: Attackers can modify unintended database columns by sending extra parameters in requests, if Eloquent models are not properly protected against mass assignment.
• Framework Contribution: Eloquent ORM's mass assignment feature, designed for developer convenience, becomes a vulnerability when $fillable or $guarded model properties are not correctly configured, directly exposing this attack surface.
• Example: A user sends a request to update their profile, including an unexpected is_admin parameter. If the User model's $fillable or $guarded attributes are not properly set, this parameter could be inadvertently assigned, leading to privilege escalation.
• Impact: Unauthorized data modification, privilege escalation, potential account takeover.
• Risk Severity: High
• Mitigation Strategies:
  • Strictly Define $fillable: Explicitly list attributes that can be mass-assigned in your Eloquent models. This is the recommended approach.
  • Use $guarded with Caution: Define attributes that should never be mass-assigned. Use this carefully and ensure it covers all sensitive attributes.
  • Request Validation is Crucial: Always validate all incoming request data and only process validated parameters, regardless of mass assignment protection.
  • Avoid Bypassing Protection in Production: Refrain from using forceFill() and unguard() in production code as they completely disable mass assignment protection.

Attack Surface: Server-Side Template Injection (SSTI) via Blade

• Description: Attackers inject malicious code into Blade template expressions that are then executed server-side, potentially leading to Remote Code Execution (RCE).
• Framework Contribution: Blade templating engine, while designed with automatic output escaping as a security feature, introduces SSTI as a potential attack surface when developers utilize raw output directives ({!! !!}) or @unescaped without rigorous sanitization. The framework provides these features, creating the possibility of SSTI if misused.
• Example: A developer uses {!! request()->input('user_provided_data') !!} in a Blade template to display user input without sanitization. An attacker could inject Blade or PHP code within user_provided_data, leading to arbitrary code execution on the server.
• Impact: Remote Code Execution (RCE), complete server compromise, data breach, full application control.
• Risk Severity: Critical
• Mitigation Strategies:
  • Minimize Raw Output Usage: Avoid using raw output ({!! !!}) and @unescaped directives in Blade templates unless absolutely necessary. Prefer the default escaping ({{ }}).
  • Rigorous Sanitization for Raw Output: If raw output is unavoidable, meticulously sanitize and validate the data before it is passed to the raw output directives. Ensure it cannot contain any executable code.
  • Content Security Policy (CSP): Implement CSP headers to limit the impact of successful SSTI by controlling the sources from which the browser can load resources, reducing the attacker's ability to inject malicious scripts.
  • Regular Template Security Audits: Conduct regular security reviews of Blade templates, specifically focusing on areas where raw output is used, to identify and remediate potential SSTI vulnerabilities.

Attack Surface: SQL Injection via Raw Queries

• Description: Attackers inject malicious SQL code into database queries, allowing them to bypass security measures, access unauthorized data, modify data, or potentially execute operating system commands.
• Framework Contribution: While Laravel's Eloquent ORM and Query Builder are designed to prevent SQL injection through parameter binding, the framework still allows developers to use raw database queries (DB::raw(), query(), etc.). This capability, while sometimes necessary for complex queries, directly introduces the risk of SQL injection if raw queries are constructed insecurely with unsanitized user input. The framework's flexibility in allowing raw queries is the contributing factor.
• Example: A developer constructs a raw query using user input directly: DB::raw("SELECT * FROM users WHERE username = '" . request()->input('username') . "'"). An attacker could input ' OR '1'='1 -- as the username, bypassing authentication and potentially retrieving all user data.
• Impact: Data breach, data manipulation, unauthorized access to sensitive information, potential server compromise depending on database permissions.
• Risk Severity: Critical
• Mitigation Strategies:
  • Prioritize Eloquent and Query Builder: Favor using Eloquent ORM and Query Builder for database interactions as they inherently use parameter binding, mitigating SQL injection risks in most scenarios.
  • Parameterized Queries for Raw SQL: If raw SQL queries are absolutely necessary for complex operations, always use parameterized queries or prepared statements to bind user input as parameters. This prevents the interpretation of user input as SQL code.
  • Input Validation and Sanitization (Defense in Depth): While parameterized queries are the primary defense, still validate and sanitize user input before using it in any database query as a secondary layer of defense and to prevent other types of injection or logic errors.
  • Principle of Least Privilege (Database Permissions): Configure database user permissions to adhere to the principle of least privilege. Limit database users to only the necessary permissions, reducing the potential damage from a successful SQL injection attack.

Attack Surface: Debug Mode Enabled in Production

• Description: Running a Laravel application with debug mode enabled in a production environment exposes sensitive application details in error pages, which can be valuable to attackers for reconnaissance and further exploitation.
• Framework Contribution: Laravel's environment configuration system, controlled by the APP_DEBUG environment variable, directly dictates whether debug mode is active. The ease of configuration and potential oversight in production deployment directly contribute to this attack surface if debug mode is unintentionally left enabled.
• Example: An attacker triggers an error in a production Laravel application with debug mode enabled. The resulting error page reveals detailed stack traces, application configuration paths, database credentials (potentially), and environment variables, providing attackers with significant information to plan further attacks.
• Impact: Information disclosure of sensitive application details, facilitating further attacks, increased risk of data breach and server compromise.
• Risk Severity: High
• Mitigation Strategies:
  • Ensure Debug Mode is Disabled in Production: Strictly enforce APP_DEBUG=false in the .env file or environment variables for all production environments. This is a critical configuration step for production deployments.
  • Implement Robust Centralized Logging: Set up comprehensive logging to capture errors and application events for debugging and monitoring purposes. This replaces the need for debug mode in production for error analysis.
  • Custom Error Pages for Production: Configure custom error pages that display user-friendly error messages to end-users in production, without revealing any technical or sensitive details.
  • Automated Configuration Checks: Implement automated checks in deployment pipelines to verify that debug mode is disabled and other security-sensitive configurations are correctly set for production environments.
  • Regular Security Configuration Reviews: Periodically review the application's configuration, especially environment settings, to ensure debug mode remains disabled and other security configurations are appropriate for production.