mitigations.md

Mitigation Strategies Analysis for getgrav/grav

Mitigation Strategy: Careful Plugin/Theme Selection and Management

Mitigation Strategy: Rigorous selection, updating, and removal of unused plugins and themes. This is the most important Grav-specific mitigation.

Description:

1. Selection: Before installing any plugin or theme:
   • Check its source. Prefer the official Grav repository or well-known, reputable developers.
   • Examine the "Last Updated" date. Avoid plugins/themes that haven't been updated in a long time (e.g., over a year).
   • Read reviews and community feedback. Look for reports of security issues or instability.
   • If possible, briefly review the plugin/theme's code. Look for red flags like direct database queries, eval(), or insecure file handling.
2. Updating:
   • Enable automatic update checks in Grav's admin panel.
   • Immediately update Grav core, plugins, and themes after any new release. Do not delay updates. Use Grav's built-in update mechanism.
   • Subscribe to the Grav newsletter and any relevant plugin/theme developer newsletters or forums to receive security alerts.
3. Removal:
   • Identify any plugins or themes that are not actively used.
   • Completely remove them from the user/plugins and user/themes directories. Disabling is not sufficient. Use Grav's admin panel or manually delete the directories.

Threats Mitigated:

• Remote Code Execution (RCE) via Plugin/Theme Vulnerability (Severity: Critical): A vulnerable plugin or theme could allow an attacker to execute arbitrary code on the server.
• Cross-Site Scripting (XSS) via Plugin/Theme Vulnerability (Severity: High): A vulnerable plugin or theme could inject malicious JavaScript.
• Privilege Escalation via Plugin/Theme Vulnerability (Severity: High): A vulnerable plugin could allow unauthorized access to the Grav admin panel.
• Information Disclosure via Plugin/Theme Vulnerability (Severity: Medium): A vulnerable plugin or theme could leak sensitive information.

Impact:

• RCE: Risk significantly reduced.
• XSS: Risk significantly reduced.
• Privilege Escalation: Risk significantly reduced.
• Information Disclosure: Risk significantly reduced.

Currently Implemented: (Example: Partially - We update regularly, but haven't thoroughly reviewed all plugin code.) <-- YOU FILL THIS IN

Missing Implementation: (Example: We need to implement a more formal process for reviewing plugin code before installation.) <-- YOU FILL THIS IN

Mitigation Strategy: Secure Grav Configuration and Feature Management

Mitigation Strategy: Properly configure Grav settings within the admin panel and YAML files, and disable unnecessary features.

Description:

1. Configuration Review (Admin Panel & YAML):
   • Use the Grav admin panel to review and configure settings.
   • Carefully review all YAML files in user/config, especially system.yaml and security.yaml.
   • Ensure security.yaml has a strong, randomly generated salt. This is set during installation but should be verified.
   • Set system.yaml -> debugger: enabled: false in production. This is a critical Grav-specific setting.
   • Review and configure uploads_dangerous_extensions in security.yaml. This is Grav's built-in (but basic) file upload restriction.
2. Feature Disablement (Admin Panel):
   • Use the Grav admin panel to disable any Grav features (e.g., specific caching methods, unused plugins) that are not essential.
3. Admin Path Change:
   • Change the default admin path from /admin to a less predictable path in system.yaml (e.g., /my-secret-admin). This is a Grav-specific configuration change.

Threats Mitigated:

• Information Disclosure via Configuration Files (Severity: High): Incorrect settings could expose sensitive information.
• Privilege Escalation via Debugger (Severity: High): The debugger, if enabled in production, can expose sensitive information and allow attackers to gain control.
• Various Attacks via Misconfiguration (Severity: Variable): Incorrect configuration settings can create various vulnerabilities.

Impact:

• Information Disclosure: Risk reduced by ensuring correct settings.
• Privilege Escalation: Risk eliminated by disabling the debugger in production.
• Various Attacks: Risk reduced by ensuring correct configuration and disabling unnecessary features.

Currently Implemented: (Example: We have disabled the debugger, but haven't changed the default admin path.) <-- YOU FILL THIS IN

Missing Implementation: (Example: We need to change the default admin path and document our configuration review process.) <-- YOU FILL THIS IN

Mitigation Strategy: Strict File Upload Handling (Using Grav's Features)

Mitigation Strategy: Utilize Grav's built-in file upload restrictions and, if developing custom plugins, implement robust validation.

Description:

1. uploads_dangerous_extensions:
   • Use Grav's uploads_dangerous_extensions setting in security.yaml to define a list of disallowed file extensions. This is a baseline and should be as restrictive as possible.
2. Custom Plugin Validation (If Applicable):
   • If you are developing a custom plugin that handles file uploads, you must implement robust server-side validation within the plugin's PHP code. This is not handled automatically by Grav.
   • Check:
     • Content Type (MIME Type): Use PHP's finfo_file() or a similar reliable method.
     • File Extension: Compare against a whitelist of allowed extensions.
     • Magic Numbers (File Signatures): Check the file's header bytes.
   • Reject any file that doesn't match all criteria.
   • Rename uploaded files to randomly generated names within your plugin's code.

Threats Mitigated:

• Remote Code Execution (RCE) via Malicious File Upload (Severity: Critical): Attackers could upload a PHP shell.
• Cross-Site Scripting (XSS) via Malicious File Upload (Severity: High): Attackers could upload an HTML file with malicious JavaScript.

Impact:

• RCE: Risk reduced by using uploads_dangerous_extensions and significantly reduced by implementing robust validation in custom plugins.
• XSS: Risk reduced similarly to RCE.

Currently Implemented: (Example: We use uploads_dangerous_extensions, but have a custom plugin that needs review.) <-- YOU FILL THIS IN

Missing Implementation: (Example: We need to thoroughly review and update the file upload handling in our custom plugin.) <-- YOU FILL THIS IN

Mitigation Strategy: Preventing File Inclusion Vulnerabilities (Within Grav and Plugins)

Mitigation Strategy: Avoid dynamic file inclusion based on user input within Twig templates and plugin code. Whitelist allowed files if necessary.

Description:

1. Avoid Dynamic Inclusion (Twig & PHP):
   • Do not use user-supplied data directly in Twig's include statements or PHP's include/require. This applies to both core Grav templates and any custom plugins you develop.
   • Example of bad code (Twig): {% include page_name ~ '.html.twig' %} (where page_name comes from user input)
   • Example of bad code (PHP - within a plugin): include($_GET['page'] . '.php');
2. Whitelisting (If Necessary):
   • If dynamic inclusion is absolutely necessary (rarely the case), create a whitelist of allowed file paths within your PHP code (plugin or page logic).

     $allowed_pages = [
         'home' => 'templates/home.html.twig',
         'about' => 'templates/about.html.twig',
     ];
     $page = $_GET['page'];
     if (isset($allowed_pages[$page])) {
         include($allowed_pages[$page]); // Safe
     }

3. Sanitization (Within Plugin Code):
   • If user input must be used to construct a file path (again, avoid this if possible), sanitize it thoroughly within your PHP code:
     • Use basename() and realpath().
     • Remove malicious characters.

Threats Mitigated:

• Local File Inclusion (LFI) (Severity: High): Attackers could include local files.
• Direct File Inclusion (DFI) (Severity: High): Similar to LFI.

Impact:

• LFI/DFI: Risk significantly reduced by avoiding dynamic inclusion and using whitelisting/sanitization where absolutely necessary.

Currently Implemented: (Example: We avoid dynamic inclusion in Twig, but need to audit all plugin code.) <-- YOU FILL THIS IN

Missing Implementation: (Example: We need to conduct a thorough code review of all plugins to identify and fix any instances of dynamic inclusion.) <-- YOU FILL THIS IN

Mitigation Strategy: CSRF Protection (Using Grav's Form Plugin)

Mitigation Strategy: Utilize Grav's built-in form.nonce system for all forms, both in standard templates and custom plugins.

Description:

1. Twig Template:
   • Include {{ form.nonce }} within every form in your Twig templates. This is a Grav-provided function.

     <form method="post" action="...">
         {{ form.nonce }}
         <input type="text" name="my_field">
         <button type="submit">Submit</button>
     </form>

2. Form Processing (Plugin or Page):
   • In your PHP code (within a plugin or a page's event handlers), validate the nonce using Grav's form object:

     if ($form->validateNonce()) {
         // Process the form data
     } else {
         // Handle invalid nonce
     }

   • This is typically done within a plugin's onFormProcessed event or a page's onPageContentProcessed event.
3. Plugin Development:
   • If you are creating custom plugins with forms, always follow steps 1 and 2. Use Grav's built-in nonce system.

Threats Mitigated:

• Cross-Site Request Forgery (CSRF) (Severity: High): Attackers could trick users into submitting unintended actions.

Impact:

• CSRF: Risk significantly reduced by using Grav's built-in nonce system correctly.

Currently Implemented: (Example: We use form.nonce in most forms, but need to verify all forms, especially in older parts of the site.) <-- YOU FILL THIS IN

Missing Implementation: (Example: We need to audit all forms to ensure form.nonce is present and validated.) <-- YOU FILL THIS IN

Mitigation Strategy: Caching (Using Grav's Built-in System)

Mitigation Strategy: Utilize and properly configure Grav's built-in caching mechanisms.

Description:

1. Configuration (Admin Panel):
   • Use the Grav admin panel to configure caching settings. This is entirely within Grav's control.
   • Choose appropriate caching levels (e.g., page caching, Twig caching) based on your content and traffic.
   • Set appropriate cache lifetimes.
2. Cache Clearing:
   • Regularly clear the cache (using the admin panel) when content is updated.

Threats Mitigated:

• Denial of Service (DoS) (Severity: Medium): Caching can reduce the load on the server, mitigating some DoS attacks.

Impact:

• DoS: Risk reduced by caching, improving performance and resilience.

Currently Implemented: (Example: We have basic caching enabled.) <-- YOU FILL THIS IN

Missing Implementation: (Example: We need to review and optimize our caching configuration for better performance.) <-- YOU FILL THIS IN

Mitigation Strategy: YAML Parsing Vulnerabilities (Reliance on Grav Updates)

Mitigation Strategy: Keep Grav updated. This relies entirely on the Grav team addressing any vulnerabilities in the underlying Symfony YAML component.

Description:

1. Keep Grav Updated:
   • This is the primary mitigation. Follow the update procedures outlined in Mitigation Strategy #1, using Grav's built-in update mechanism.

Threats Mitigated:

• Remote Code Execution (RCE) via YAML Parser Vulnerability (Severity: Critical, but very unlikely): A vulnerability in the YAML parser.

Impact:

• RCE: Risk is extremely low if Grav is kept updated.

Currently Implemented: (Example: We keep Grav updated.) <-- YOU FILL THIS IN

Missing Implementation: (Example: None, as long as we maintain our update schedule.) <-- YOU FILL THIS IN