threat-modeling.md

Threat Model Analysis for bcit-ci/codeigniter

Threat: Insecure Default Configuration

Description: Attackers might exploit default, insecure configurations left unchanged by developers. This could involve accessing debug information, using default encryption keys to decrypt data, or leveraging overly permissive file permissions to access sensitive files.

Impact: Information disclosure (sensitive configuration details, debug information), unauthorized access to application functionalities, potential for system compromise and data breaches.

CodeIgniter Component Affected: Configuration files (application/config/config.php, etc.), potentially core framework functionalities relying on configuration.

Risk Severity: High

Mitigation Strategies:

• Thoroughly review and harden all configuration settings during development and deployment.
• Disable debug mode (ENVIRONMENT) in production.
• Change default encryption keys and salts to strong, unique values.
• Implement strict file permissions for application files and directories, limiting access to only necessary users/processes.

Threat: Exposure of Configuration Files

Description: Attackers could exploit web server misconfigurations or bypass access controls to directly access configuration files like config.php or database.php. This allows them to read sensitive information directly from the files.

Impact: Critical information disclosure including database credentials, encryption keys, API secrets, and other sensitive application settings. This can lead to full application compromise and data breaches.

CodeIgniter Component Affected: Web server configuration, file system access, configuration files (application/config/).

Risk Severity: Critical

Mitigation Strategies:

• Configure the web server (Apache, Nginx, IIS) to prevent direct access to application files and directories, especially the application/ directory.
• Utilize .htaccess (Apache) or web.config (IIS) to explicitly deny access to configuration files.
• Consider storing configuration files outside the web root directory for enhanced security.

Threat: Improper Use of Database Abstraction

Description: Attackers can exploit SQL injection vulnerabilities if developers bypass CodeIgniter's query builder and write raw SQL queries with unsanitized user input. They can inject malicious SQL code to manipulate database queries.

Impact: SQL Injection vulnerabilities leading to data breaches (reading, modifying, deleting data), unauthorized access to sensitive information, potential for database server compromise, and denial of service.

CodeIgniter Component Affected: Database library, model layer, database interaction code.

Risk Severity: Critical

Mitigation Strategies:

• Always utilize CodeIgniter's query builder or prepared statements for all database interactions.
• Avoid manual string concatenation when building SQL queries.
• If raw queries are absolutely necessary (highly discouraged), meticulously sanitize and escape all user input using CodeIgniter's database escaping functions.
• Implement parameterized queries or stored procedures where appropriate.

Threat: Insufficient Input Validation (Framework Misuse)

Description: Attackers can exploit vulnerabilities like XSS, SQL Injection (if query builder is misused), or other injection attacks if developers fail to implement comprehensive input validation using CodeIgniter's validation library or other methods. They can inject malicious payloads through form fields, URL parameters, or headers.

Impact: Cross-Site Scripting (XSS) allowing attackers to execute malicious scripts in users' browsers, SQL Injection (if database abstraction is misused), other injection vulnerabilities leading to data manipulation, unauthorized actions, or system compromise.

CodeIgniter Component Affected: Input class, form validation library, controllers, models, views (if displaying unvalidated input).

Risk Severity: High

Mitigation Strategies:

• Extensively utilize CodeIgniter's form validation library to validate all user inputs on the server-side.
• Define comprehensive validation rules for each input field, including data type, length, format, and allowed values.
• Implement server-side validation even if client-side validation is present, as client-side validation can be bypassed.
• Sanitize input data before using it in any application logic, even after validation, to prevent unexpected behavior.

Threat: Inadequate Output Encoding (Framework Misuse)

Description: Attackers can inject malicious scripts into web pages if developers fail to properly encode output data before displaying it in views. This allows for Cross-Site Scripting (XSS) attacks.

Impact: Cross-Site Scripting (XSS) vulnerabilities, allowing attackers to execute malicious JavaScript in users' browsers, potentially leading to session hijacking, account takeover, website defacement, or redirection to malicious sites.

CodeIgniter Component Affected: Views, output class, potentially controllers if directly outputting data.

Risk Severity: High

Mitigation Strategies:

• Always encode output data before displaying it in views, especially user-generated content or data retrieved from databases.
• Use CodeIgniter's esc() function or other appropriate encoding functions (e.g., htmlentities(), htmlspecialchars()) for output encoding.
• Choose the correct encoding method based on the context (HTML, JavaScript, URL, etc.).
• Implement Content Security Policy (CSP) headers to further mitigate XSS risks.

Threat: Insecure Session Configuration

Description: Attackers can exploit insecure session configurations to perform session hijacking or fixation attacks. This can involve stealing session cookies, predicting session IDs, or forcing users to use a known session ID.

Impact: Session hijacking, allowing attackers to impersonate legitimate users and gain unauthorized access to user accounts and application functionalities. Session fixation, potentially leading to account takeover.

CodeIgniter Component Affected: Session library, configuration files (application/config/config.php).

Risk Severity: High

Mitigation Strategies:

• Configure session settings in application/config/config.php for optimal security.
• Use secure session drivers (e.g., database, Redis) instead of file-based sessions in production for better security and scalability.
• Enable HTTPS-only sessions ($config['cookie_secure'] = TRUE;) when using HTTPS to prevent session cookie transmission over insecure channels.
• Set $config['cookie_httponly'] = TRUE; to prevent client-side JavaScript access to session cookies, mitigating some XSS-based session theft.
• Set $config['sess_regenerate_destroy'] = TRUE; to mitigate session fixation attacks by regenerating session IDs after login.
• Consider using a strong session ID generator and regularly rotating session keys.

Threat: Session Fixation (if not properly mitigated)

Description: Attackers can attempt to fixate a user's session ID by providing them with a known session ID before they log in. If session regeneration is not properly implemented after login, the attacker can then hijack the session after the user authenticates.

Impact: Session hijacking, unauthorized access to user accounts, potentially leading to data breaches and unauthorized actions performed under the user's identity.

CodeIgniter Component Affected: Session library, authentication system, potentially controllers handling login.

Risk Severity: High

Mitigation Strategies:

• Ensure session regeneration is implemented correctly, especially immediately after successful user authentication.
• Utilize CodeIgniter's session library features for session regeneration (e.g., $this->session->sess_regenerate(TRUE);).
• Invalidate old session IDs after regeneration to prevent reuse.

Threat: Insecure File Upload Handling (Framework Misuse)

Description: Attackers can upload malicious files if developers fail to implement proper security measures for file uploads. This can lead to arbitrary file upload, path traversal, and execution of malicious code on the server.

Impact: Arbitrary file upload, allowing attackers to upload any file type to the server, potentially including web shells or malware. Remote code execution if uploaded files can be executed by the web server. Website defacement, data breaches, and denial of service.

CodeIgniter Component Affected: File upload library, controllers handling file uploads, file system.

Risk Severity: Critical

Mitigation Strategies:

• Implement strict file type validation on both client-side and server-side.
• Validate file extensions and MIME types against a whitelist of allowed types.
• Sanitize filenames to prevent path traversal attacks (e.g., removing "..", "/", "\", and other special characters).
• Store uploaded files outside the web root directory to prevent direct execution via web requests.
• Implement file size limits to prevent denial of service attacks and resource exhaustion.
• Consider using a dedicated file storage service (e.g., cloud storage) instead of storing files directly on the web server for enhanced security and scalability.
• Scan uploaded files for malware using antivirus software if handling sensitive files.

Threat: Vulnerable CodeIgniter Version

Description: Attackers can exploit known vulnerabilities present in outdated versions of CodeIgniter. Publicly disclosed vulnerabilities can be easily exploited if applications are not updated.

Impact: Various vulnerabilities depending on the specific CodeIgniter version and the nature of the vulnerability. This could range from information disclosure to remote code execution and full system compromise.

CodeIgniter Component Affected: Core framework, potentially all components depending on the vulnerability.

Risk Severity: High to Critical (depending on the vulnerability)

Mitigation Strategies:

• Keep the CodeIgniter framework updated to the latest stable version.
• Regularly check for security updates and apply them promptly.
• Subscribe to security mailing lists or follow security advisories related to CodeIgniter to stay informed about new vulnerabilities.
• Implement a vulnerability management process to track and address known vulnerabilities in the framework and dependencies.