threat-modeling.md

Threat Model Analysis for bcit-ci/codeigniter

Threat: Exposed Configuration Files

Description: An attacker could gain access to sensitive configuration files (e.g., database.php, .env) if these files are accessible via the web due to misconfiguration. Attackers can then extract credentials and sensitive information directly from these files.

Impact: Critical. Full compromise of database credentials, API keys, encryption keys, and other sensitive data. This leads to potential data breaches, unauthorized access, and complete application takeover.

CodeIgniter Component Affected: Configuration Files (application/config/) and potentially .env if used with a library. Web server configuration is the entry point for this vulnerability.

Risk Severity: Critical

Mitigation Strategies:

• Move configuration files outside the web root directory.
• Configure web server to explicitly deny access to configuration files.
• Use strict file permissions (e.g., 600 or 640) for configuration files, readable only by the web server user.
• Utilize environment variables instead of storing sensitive data directly in configuration files.
• Regularly audit web server and file system configurations.

Threat: Debug Mode Enabled in Production

Description: Leaving CodeIgniter's debug mode enabled in production (ENVIRONMENT set to 'development' or 'testing' in index.php) exposes detailed error messages and debugging information. Attackers can leverage this information to understand the application's structure, identify vulnerabilities, and plan targeted attacks.

Impact: High. Information disclosure significantly aiding attackers in finding and exploiting vulnerabilities. Performance degradation in production. Error messages can reveal sensitive file paths, database queries, and code logic.

CodeIgniter Component Affected: index.php (Environment setting), CodeIgniter Error Handling.

Risk Severity: High

Mitigation Strategies:

• Ensure ENVIRONMENT is set to 'production' in index.php for all production deployments.
• Implement robust error logging to secure locations and display generic error pages to users in production.
• Regularly audit application configuration to verify debug mode is disabled in production.

Threat: Insecure Default Session Configuration

Description: Using default or weakly configured session management in CodeIgniter can lead to session hijacking or fixation. Attackers can exploit default session storage mechanisms or insecure cookie settings to steal or manipulate user sessions, gaining unauthorized access.

Impact: High. Unauthorized access to user accounts and application functionalities. Session hijacking allows attackers to impersonate legitimate users and perform actions on their behalf.

CodeIgniter Component Affected: Session Library (configuration in application/config/config.php, Session class).

Risk Severity: High

Mitigation Strategies:

• Harden session configuration in application/config/config.php:
  • Use a secure sess_driver such as 'database' or 'redis' instead of 'files'.
  • Set sess_cookie_secure to TRUE to enforce HTTPS for session cookies.
  • Set sess_http_only to TRUE to prevent client-side JavaScript access to session cookies.
  • Set sess_regenerate_destroy to TRUE to regenerate session IDs on login, mitigating session fixation.
  • Adjust sess_expiration to a suitable timeout value for security and usability.
• Regularly review and update session configuration based on security best practices.

Threat: Outdated CodeIgniter Version

Description: Running an outdated version of CodeIgniter exposes the application to known security vulnerabilities that have been patched in newer releases. Attackers actively target applications running vulnerable versions of frameworks to exploit these known weaknesses.

Impact: High to Critical. Exploitation of known framework vulnerabilities can lead to information disclosure, data breaches, remote code execution, and complete server compromise, depending on the specific vulnerability.

CodeIgniter Component Affected: Core CodeIgniter Framework (all components).

Risk Severity: High to Critical (depending on the age and vulnerabilities of the outdated version).

Mitigation Strategies:

• Maintain CodeIgniter up-to-date by regularly upgrading to the latest stable version.
• Subscribe to CodeIgniter security advisories and release notes to stay informed about security updates.
• Establish a process for promptly applying security patches and updates.
• Utilize dependency management tools (e.g., Composer) to streamline updates.

Threat: Improper Input Validation and Output Encoding (Framework Misuse)

Description: Developers neglecting to properly use CodeIgniter's input validation and output encoding features can introduce Cross-Site Scripting (XSS) and SQL Injection vulnerabilities. Attackers exploit these by injecting malicious code through input fields or crafted URLs, bypassing security measures that the framework provides tools to prevent.

Impact:

• XSS: High. User account compromise, session hijacking, website defacement, redirection to malicious sites, and malware distribution.
• SQL Injection: Critical. Data breaches, data modification or deletion, unauthorized access to sensitive data, and potential remote code execution on the database server.

CodeIgniter Component Affected: Input Library, Output Library (esc() function), Database Library (Query Builder), Form Validation Library.

Risk Severity: XSS: High, SQL Injection: Critical

Mitigation Strategies:

• Mandatory use of CodeIgniter's Input Library for validating all user-supplied inputs. Define and enforce appropriate validation rules for each input field.
• Enforce output encoding using CodeIgniter's esc() function in views to prevent XSS vulnerabilities. Choose the correct encoding context (HTML, JavaScript, URL, etc.) based on where the output is displayed.
• Primarily use CodeIgniter's Query Builder for database interactions to mitigate SQL Injection risks. Avoid writing raw SQL queries, especially when incorporating user input. If raw queries are necessary, use prepared statements and parameter binding.
• Conduct thorough code reviews with a focus on input validation and output encoding practices to identify and remediate vulnerabilities.

Threat: Insecure File Upload Handling (Framework Misuse)

Description: Developers may improperly implement file upload functionality, failing to utilize CodeIgniter's file upload library securely or creating custom insecure implementations. This can enable attackers to upload malicious files (e.g., web shells) and potentially gain remote code execution or deface the website. Path traversal vulnerabilities can also arise from insecure filename handling.

Impact: Critical to High. Remote code execution on the server, website defacement, server compromise, data breaches, and denial of service.

CodeIgniter Component Affected: File Upload Library, Input Library.

Risk Severity: Critical to High.

Mitigation Strategies:

• Utilize CodeIgniter's File Upload Library for handling file uploads.
• Implement strict server-side file type validation based on file extensions and MIME types, not relying solely on client-side checks.
• Sanitize uploaded filenames to prevent path traversal attacks by removing or replacing special characters and ensuring safe naming conventions.
• Store uploaded files outside the web root directory whenever possible to prevent direct execution of uploaded scripts.
• If files must be within the web root, configure the web server to explicitly prevent script execution within the upload directory (e.g., using .htaccess or Nginx configurations).
• Implement file size limits to prevent denial-of-service attacks through excessive uploads.
• Consider integrating malware scanning of uploaded files using antivirus software.

Threat: Session Fixation Vulnerability (If sess_regenerate_destroy is not enabled)

Description: If session regeneration upon login (sess_regenerate_destroy) is not enabled in CodeIgniter's session configuration, the application becomes vulnerable to session fixation attacks. An attacker can pre-set a session ID and trick a user into authenticating with it, allowing the attacker to hijack the session after successful login.

Impact: High. Session hijacking and unauthorized access to user accounts, enabling attackers to impersonate legitimate users.

CodeIgniter Component Affected: Session Library (configuration in application/config/config.php, Session class).

Risk Severity: High

Mitigation Strategies:

• Ensure sess_regenerate_destroy is set to TRUE in application/config/config.php to enable session ID regeneration on login.
• Verify that session IDs are always regenerated upon successful user authentication to prevent session fixation.