threat-modeling.md

Threat Model Analysis for ryanb/cancan

Threat: Missing CanCan Authorization Checks in Controllers

• Description: Attacker directly accesses controller actions that lack authorize! or load_and_authorize_resource. They can manipulate requests to trigger these unprotected actions, bypassing intended authorization.
• Impact: Unauthorized data modification, deletion, or access to sensitive information. Potential data breach and system compromise.
• CanCan Component Affected: Controller integration (specifically the absence of authorize! and load_and_authorize_resource calls).
• Risk Severity: High
• Mitigation Strategies:
  • Implement mandatory code reviews focusing on authorization checks in controllers.
  • Utilize static analysis tools or linters to detect missing authorize! calls.
  • Establish coding standards requiring authorization checks for all relevant controller actions.
  • Implement integration tests to verify authorization enforcement for all controller actions.
  • Consider using a base controller to enforce default authorization, requiring explicit opt-out for public actions.

Threat: Incorrectly Defined Abilities

• Description: Attacker exploits flaws in the logic of ability.rb definitions. They identify overly permissive rules or incorrect conditions that grant them unintended access or actions. They then craft requests to leverage these loopholes.
• Impact: Privilege escalation, allowing users to perform actions beyond their intended roles. Data breaches due to unauthorized access and manipulation.
• CanCan Component Affected: ability.rb (Ability definition logic).
• Risk Severity: High
• Mitigation Strategies:
  • Conduct thorough reviews and testing of ability definitions, especially complex conditions.
  • Write unit tests specifically for ability definitions, covering various user roles and scenarios (positive and negative cases).
  • Use clear and specific conditions in ability rules, avoiding overly generic rules.
  • Regularly audit and update ability definitions as application features and user roles evolve.

Threat: Bypassing CanCan Checks through Direct Database Manipulation

• Description: Attacker identifies and exploits application components that directly interact with the database without going through CanCan-protected controllers (e.g., background jobs, custom scripts, API endpoints with flawed authorization). They can then manipulate data directly, bypassing CanCan's intended authorization.
• Impact: Complete bypass of authorization, allowing attackers to directly manipulate data regardless of CanCan rules. Data integrity compromise and potential system takeover.
• CanCan Component Affected: Application integration (failure to consistently apply CanCan across all data access points).
• Risk Severity: Critical
• Mitigation Strategies:
  • Ensure all data access points, including background jobs, APIs, and custom queries, are integrated with CanCan or a similar authorization mechanism.
  • Minimize or eliminate direct database manipulation outside of the application's intended access paths.
  • Conduct security audits to identify potential bypasses outside of standard controller actions.

Threat: Overly Permissive Default Abilities

• Description: Attacker benefits from overly broad default abilities defined in ability.rb (e.g., starting with can :manage, :all). They exploit these defaults to gain unintended permissions, even if specific restrictions are intended later but are insufficient or flawed.
• Impact: Unintentional privilege escalation, allowing regular users to perform administrative actions or access sensitive data. System compromise and data breaches.
• CanCan Component Affected: ability.rb (Default ability definitions).
• Risk Severity: High
• Mitigation Strategies:
  • Adopt the principle of least privilege when defining abilities. Start with restrictive defaults and explicitly grant permissions as needed.
  • Avoid using can :manage, :all as a starting point unless absolutely necessary and immediately followed by robust and well-tested cannot rules.
  • Regularly review default ability definitions to ensure they remain appropriate as the application evolves.