mitigations.md

Mitigation Strategies Analysis for railsadminteam/rails_admin

Mitigation Strategy: Robust Authorization within rails_admin (CanCanCan/Pundit Integration)

• Description:

  1. Install CanCanCan or Pundit: Choose either CanCanCan or Pundit for authorization. Install the chosen gem.
  2. Define Abilities/Policies:
     • CanCanCan: Create an Ability class (usually app/models/ability.rb) that defines user permissions specifically for rails_admin actions. Use can and cannot methods to specify which actions users can perform on which models within the rails_admin context. This is crucial: you're defining what's allowed within the admin interface, not the entire application.

       class Ability
         include CanCan::Ability
       
         def initialize(user)
           user ||= User.new # guest user (not logged in)
       
           if user.role == 'editor'
             can :manage, Article, :rails_admin => true # Can perform any action on Article *in rails_admin*
             can :read, User, :rails_admin => true # Can only read User records *in rails_admin*
             cannot :destroy, User, :rails_admin => true # Cannot delete User records *in rails_admin*
           elsif user.role == 'viewer'
             can :read, :all, :rails_admin => true # Can read all models *in rails_admin*
           else
             # No permissions for guest users in rails_admin
           end
         end
       end

     • Pundit: Create policy classes for each model (e.g., app/policies/article_policy.rb). Define methods corresponding to rails_admin actions (e.g., show?, create?, update?, destroy?). These methods return true or false based on the user and the resource, specifically considering the rails_admin context. You might need to add a context check within your policies.

       class ArticlePolicy < ApplicationPolicy
         def rails_admin?(action) # Custom method to check for rails_admin context
           context[:controller].is_a?(RailsAdmin::MainController) && send("#{action}?")
         end
       
         def show?
           true # Everyone can view articles (even outside rails_admin)
         end
       
         def create?
           user.role == 'editor' || user.role == 'admin'
         end
       
         def update?
           create? # Same permissions as create
         end
       
         def destroy?
           user.role == 'admin'
         end
       end

  3. Configure rails_admin with Authorization: In config/initializers/rails_admin.rb, set config.authorize_with to use CanCanCan or Pundit. For example:

     config.authorize_with :cancancan # Or :pundit

  4. Regularly Review and Update: Periodically review the abilities/policies to ensure they remain aligned with the principle of least privilege within rails_admin.

• Threats Mitigated:

  • Privilege Escalation (High Severity): Prevents authenticated users from performing actions they are not authorized to do within rails_admin (e.g., a "viewer" deleting records through the admin interface). This is the core threat this mitigation addresses.
  • Unauthorized Access (High Severity): While overall authentication is handled separately (e.g., by Devise), this ensures that even if a user is authenticated, they can't do anything in rails_admin without explicit permission.

• Impact:

  • Privilege Escalation: Risk significantly reduced; users are limited to their defined permissions within the rails_admin interface.
  • Unauthorized Access: Provides a crucial layer of defense within rails_admin, ensuring that even authenticated users are restricted.

• Currently Implemented:

  • CanCanCan is implemented with abilities defined in app/models/ability.rb.
  • rails_admin is configured to use CanCanCan in config/initializers/rails_admin.rb.

• Missing Implementation:

  • Regular (quarterly) reviews of the Ability class are not formally scheduled, specifically focusing on the :rails_admin => true context.

Mitigation Strategy: Disable Unused rails_admin Features

• Description:

  1. Identify Unused Features: Review the rails_admin documentation and identify features that are not being used in your application (e.g., history, bulk actions, specific model actions, export options). This is a rails_admin-specific task.
  2. Disable in Configuration: In config/initializers/rails_admin.rb, use the configuration options to disable the identified features. This is done entirely within the rails_admin configuration.

     RailsAdmin.config do |config|
       config.actions do
         dashboard                     # mandatory
         index                         # mandatory
         new
         export  do
             except ['User', 'SensitiveModel'] #disable for some models
         end
         bulk_delete do
             except ['User'] #disable for some models
         end
         show
         edit
         delete
         # history_index # Disable history index
         # history_show # Disable history show
       end
     
       # config.excluded_models = ['SecretModel'] # Completely hide a model from rails_admin
     
       config.model 'Article' do
         edit do
           # exclude_fields :created_at, :updated_at # Hide fields within rails_admin
         end
       end
     end

  3. Test Functionality: After disabling features, thoroughly test the remaining rails_admin functionality to ensure it works as expected.

• Threats Mitigated:

  • Unknown Vulnerabilities in Unused Features (Unknown Severity): Reduces the rails_admin-specific attack surface by removing potentially vulnerable code that is not being used.
  • Accidental Misuse (Low Severity): Prevents users from accidentally triggering rails_admin actions that are not intended to be used.

• Impact:

  • Unknown Vulnerabilities: Risk reduced; fewer potential vulnerabilities within rails_admin.
  • Accidental Misuse: Risk reduced; fewer actions available to users within rails_admin.

• Currently Implemented:

  • History features are disabled in config/initializers/rails_admin.rb.
  • Export is disabled for specific models in config/initializers/rails_admin.rb.

• Missing Implementation:

  • A comprehensive review of all rails_admin features has not been conducted to identify all unused features. This should be done periodically, focusing specifically on the rails_admin configuration.

Mitigation Strategy: Custom Field Validation within rails_admin (Beyond Model Validations)

• Description:

  1. Identify Sensitive Fields: Identify fields within the rails_admin interface that handle sensitive data or are particularly vulnerable to injection attacks.
  2. Add rails_admin-Specific Validations: Within the rails_admin configuration (config/initializers/rails_admin.rb) for the relevant models and fields, use the validates option to add custom validation logic. This validation is specific to the rails_admin interface and supplements model-level validations.

     RailsAdmin.config do |config|
       config.model 'Article' do
         edit do
           field :title do
             validates do # This is rails_admin specific validation
               length maximum: 100
               format with: /\A[a-zA-Z0-9\s]+\z/, message: "Only letters, numbers, and spaces allowed"
             end
           end
           field :external_link, :string do
             validates do # This is rails_admin specific validation
               format with: URI::regexp(%w(http https)), message: "Must be a valid URL"
             end
           end
         end
       end
     end

  3. Test Validations: Thoroughly test the custom validations within the rails_admin interface to ensure they correctly reject invalid input and allow valid input.

• Threats Mitigated:

  • Cross-Site Scripting (XSS) (High Severity): Prevents malicious JavaScript code from being injected into fields through the rails_admin interface.
  • SQL Injection (High Severity): While Rails' ORM protects against most SQL injection, custom validations within rails_admin provide an extra layer of defense.
  • Invalid Data Input (Medium Severity): Ensures that data entered through rails_admin conforms to specific formats and constraints.

• Impact:

  • XSS: Risk reduced; custom validations within rails_admin can catch XSS attempts that might bypass model-level validations.
  • SQL Injection: Risk further reduced (defense-in-depth) specifically for input through rails_admin.
  • Invalid Data: Risk reduced; data quality is improved for data entered via rails_admin.

• Currently Implemented:

  • Basic length validations are present on some text fields in config/initializers/rails_admin.rb.

• Missing Implementation:

  • Comprehensive custom validations are not in place for all relevant fields within the rails_admin configuration. A systematic review of all fields and the addition of appropriate validations (especially regular expressions for format validation) is needed, specifically within the rails_admin.rb initializer.

Mitigation Strategy: Careful Use of formatted_value within rails_admin

• Description:

  1. Avoid formatted_value When Possible: Prefer using built-in rails_admin field types and formatting options instead of custom formatted_value implementations. This is a rails_admin-specific recommendation.
  2. If Necessary, Sanitize Thoroughly: If you must use formatted_value within a rails_admin configuration, ensure that any user-provided data included in the output is properly escaped or sanitized to prevent XSS vulnerabilities. This sanitization happens within the rails_admin configuration.

     RailsAdmin.config do |config|
       config.model 'Comment' do
         list do
           field :body do
             formatted_value do # This is within the rails_admin configuration
               # VERY BAD (vulnerable to XSS):
               # bindings[:view].raw(value)
     
               # BETTER (escapes HTML):
               bindings[:view].h(value)
     
               # BEST (allows specific HTML tags):
               # bindings[:view].sanitize(value, tags: %w(strong em a), attributes: %w(href))
             end
           end
         end
       end
     end

  3. Test for XSS: After implementing formatted_value within rails_admin, test for XSS vulnerabilities by attempting to inject malicious JavaScript code into the relevant fields through the rails_admin interface.

• Threats Mitigated:

  • Cross-Site Scripting (XSS) (High Severity): Prevents malicious JavaScript code from being executed in the context of the rails_admin interface.

• Impact:

  • XSS: Risk significantly reduced if formatted_value is used correctly with proper sanitization within rails_admin.

• Currently Implemented:

  • formatted_value is not currently used in the project.

• Missing Implementation:

  • A policy should be documented to strongly discourage the use of formatted_value within rails_admin configurations unless absolutely necessary and with thorough sanitization.

Mitigation Strategy: Keep rails_admin Gem Updated

• Description: This is directly related to the security of the rails_admin gem itself.

  1. Monitor for Updates: Regularly check the rails_admin GitHub repository or RubyGems page for new releases.
  2. Update the Gem: When a new version is available, update the rails_admin gem in your Gemfile and run bundle update rails_admin.
  3. Test After Update: After updating, thoroughly test rails_admin and your application to ensure that the update did not introduce any regressions or compatibility issues.

• Threats Mitigated:

  • Known Vulnerabilities in rails_admin (Variable Severity): Updates often include patches for security vulnerabilities that have been discovered and fixed specifically within the rails_admin gem.

• Impact:

  • Known Vulnerabilities: Risk reduced; patched versions address known security issues within rails_admin.

• Currently Implemented:

  • The Gemfile specifies rails_admin, and bundle update is run regularly.

• Missing Implementation:

  • A formal process for monitoring rails_admin releases (e.g., subscribing to release notifications) is not in place.