Skip to content

Latest commit

 

History

History
79 lines (70 loc) · 5.5 KB

attack-tree.md

File metadata and controls

79 lines (70 loc) · 5.5 KB

Attack Tree Analysis for varvet/pundit

Objective: To perform unauthorized actions on resources within the application by circumventing or misusing Pundit's authorization policies.

Attack Tree Visualization

                                      Unauthorized Action Execution
                                                  |
                      -------------------------------------------------------------------
                      |                                   |
              Incorrect Policy Logic [HR]         Bypassing Policy Checks [HR]
                      |                                   |
      -----------------------------------     -----------------------------------
      |                 |                 |     |                 |
Missing Scope     Flawed Scope     Incorrect    Missing       Incorrect     Abusing
Resolution [CN] Implementation  Conditional   `authorize`   `authorize`   Policy
                      Logic         Calls [CN]   Placement [CN] Scope [CN]

Attack Tree Path: Incorrect Policy Logic [HR]

  • Description: The policy itself contains flaws that allow unauthorized access, even when Pundit is technically used correctly. This is a high-risk path because it represents a fundamental error in the authorization logic.
  • Sub-Vectors:
    • Missing Scope Resolution [CN]:
      • Description: The policy_scope method (used for scoping collections of resources) is either missing or returns an overly permissive scope. This is a critical node due to its high likelihood and potential for significant data exposure.
      • Likelihood: Medium
      • Impact: High to Very High
      • Effort: Low
      • Skill Level: Novice to Intermediate
      • Detection Difficulty: Medium
      • Mitigation: Ensure every policy has a well-defined policy_scope method. Thoroughly test the scope resolution to ensure it only returns authorized records. Use test cases that cover edge cases.
    • Flawed Scope Implementation:
      • Description: The logic within policy_scope is incorrect (e.g., incorrect database query, misinterpretation of user roles).
      • Likelihood: Medium
      • Impact: High to Very High
      • Effort: Low to Medium
      • Skill Level: Intermediate
      • Detection Difficulty: Medium to Hard
      • Mitigation: Review the SQL/ActiveRecord queries within policy_scope for correctness. Use a debugger to step through the logic. Write unit tests specifically for policy_scope.
    • Incorrect Conditional Logic:
      • Description: Policy methods (e.g., show?, create?) contain incorrect conditional logic (wrong attributes, incorrect boolean operators, failure to handle edge cases).
      • Likelihood: Medium
      • Impact: Medium to Very High
      • Effort: Low
      • Skill Level: Novice to Intermediate
      • Detection Difficulty: Medium
      • Mitigation: Carefully review the logic within each policy method. Write comprehensive unit tests for each policy method, covering all code paths and edge cases. Use a code coverage tool.

Attack Tree Path: Bypassing Policy Checks [HR]

  • Description: The attacker finds a way to execute actions without triggering Pundit's authorization checks. This is a high-risk path because it represents a complete bypass of the intended security mechanism.
  • Sub-Vectors:
    • Missing authorize Calls [CN]:
      • Description: The developer forgets to call authorize (or authorize!) in a controller action or other relevant location. This is the most critical node due to its high likelihood, very high impact, and ease of exploitation.
      • Likelihood: High
      • Impact: Very High
      • Effort: Very Low
      • Skill Level: Novice
      • Detection Difficulty: Medium to Hard
      • Mitigation: Establish a coding standard requiring authorize calls. Use code review and potentially linters/static analysis tools. Implement integration tests.
    • Incorrect authorize Placement [CN]:
      • Description: authorize is called, but in the wrong place (e.g., after a database modification). This is a critical node because it can lead to unauthorized actions before authorization is checked.
      • Likelihood: Medium
      • Impact: High to Very High
      • Effort: Very Low
      • Skill Level: Novice
      • Detection Difficulty: Medium to Hard
      • Mitigation: Ensure authorize is called before any potentially unauthorized action. Use code review and testing.
    • Abusing Policy Scope [CN]:
      • Description: The attacker manipulates input parameters to influence the policy_scope to return more records than intended (parameter tampering). This is a critical node due to its potential for significant data exposure and relative difficulty of detection.
      • Likelihood: Medium
      • Impact: High to Very High
      • Effort: Medium
      • Skill Level: Intermediate
      • Detection Difficulty: Medium to Hard
      • Mitigation: Validate and sanitize all input parameters used within policy_scope. Avoid directly using user-supplied data in database queries without proper escaping. Use strong parameters.