Patch Artifact Specification

finding_ref:
  finding_id: FD-SHOP-AUTHZ-001
  invariant: INV-SHOP-OWNER-DELETE
  scenario: S-SHOP-IDOR-DELETE-001
  exploration: E-SHOP-IDOR-DELETE-001-01
  impact: "Any authenticated user could delete items belonging to other users"

root_cause:
  issue: |
    The delete endpoint extracted item_id from the URL but did not verify
    that the authenticated user owned the item before deletion. The ownership
    check was accidentally removed during refactoring in commit abc123.
  code_locations:
    - file: "src/api/items.py"
      line: 42
      function: "delete_item"
      snippet: "item = Item.query.get(item_id)  # Missing: check user == item.owner"
  pattern: "Missing authorization check on resource operations"
  contributing_factors:
    - "No unit test for ownership verification"
    - "Code review did not catch missing check"
    - "Authorization logic not centralized"

verification:
  explorations_rerun:
    - exploration_id: E-SHOP-IDOR-DELETE-001-01
      result_before: VIOLATED
      result_after: HOLDS
      notes: "UserB can no longer delete UserA's items"
    - exploration_id: E-SHOP-IDOR-DELETE-001-02
      result_before: VIOLATED
      result_after: HOLDS
      notes: "Verified with admin user as well"
  additional_tests:
    - "Tested with edge case: owner deleting own item (should succeed)"
    - "Tested with non-existent item_id (should 404, not leak info)"
  verified_by: "security-team"
  verified_at: "2024-01-15T14:30:00Z"

id: PATCH-SHOP-001
title: "Fix ownership checks on item delete()"
 
finding_ref:
  finding_id: FD-SHOP-AUTHZ-001
  invariant: INV-SHOP-OWNER-DELETE
  scenario: S-SHOP-IDOR-DELETE-001
  exploration: E-SHOP-IDOR-DELETE-001-01
  impact: "Any authenticated user could delete items belonging to other users"
 
root_cause:
  issue: |
    The delete_item endpoint extracted item_id from the URL path but did not
    verify that the authenticated user owned the item before deletion. The
    ownership check was present in the update endpoint but missing from delete.
  code_locations:
    - file: "src/api/items.py"
      line: 42
      function: "delete_item"
      snippet: |
        @app.route('/items/<item_id>', methods=['DELETE'])
        def delete_item(item_id):
            item = Item.query.get(item_id)
            # BUG: Missing ownership check here
            db.session.delete(item)
  pattern: "Missing authorization check on destructive operations"
  contributing_factors:
    - "Copy-paste from read endpoint without auth check"
    - "No integration test for ownership on delete"
 
fix_description: |
  Added ownership verification to the delete_item endpoint. Before deleting,
  the endpoint now checks that the authenticated user's ID matches the item's
  owner_id. Returns 403 Forbidden if the user is not the owner.
 
code_changes:
  - file: "src/api/items.py"
    description: "Added ownership check before delete"
    change_type: modified
    commit: "abc123def456"
    pull_request: "https://github.com/example/shop/pull/42"
  - file: "tests/test_items.py"
    description: "Added integration test for ownership on delete"
    change_type: modified
 
verification:
  explorations_rerun:
    - exploration_id: E-SHOP-IDOR-DELETE-001-01
      result_before: VIOLATED
      result_after: HOLDS
      notes: "UserB receives 403 when trying to delete UserA's items"
    - exploration_id: E-SHOP-IDOR-DELETE-001-02
      result_before: VIOLATED
      result_after: HOLDS
      notes: "Admin user also cannot delete non-owned items"
  additional_tests:
    - "Owner successfully deletes own item"
    - "Non-existent item returns 404"
    - "Unauthenticated request returns 401"
  verified_by: "security-team"
  verified_at: "2024-01-15T14:30:00Z"
 
validation:
  regression_tests:
    - "test_delete_own_item_succeeds"
    - "test_delete_other_user_item_forbidden"
    - "test_delete_nonexistent_item_not_found"
  edge_cases:
    - "Item with no owner field (legacy data)"
    - "Concurrent delete requests"
  reviewed_by:
    - "alice@example.com"
    - "bob@example.com"
 
vaccination:
  change_type: middleware
  description: |
    Created centralized @require_ownership decorator that can be applied to
    any endpoint that operates on owned resources. This decorator extracts
    the resource ID, loads the resource, and verifies ownership before
    allowing the request to proceed.
  new_invariants: []
  strengthened_invariants:
    - INV-SHOP-OWNER-DELETE
  automation:
    - "Added linting rule to flag endpoints without @require_auth or @require_ownership"
  scope: "All shop resource endpoints"
 
valuation:
  metrics:
    blocked_exploit_attempts: 0
    test_coverage_increase: "15%"
    endpoints_protected: 12
  status_overlay_updates:
    - invariant: INV-SHOP-OWNER-DELETE
      scope: "/api/items/*"
      previous_status: KNOWN_MISSING
      new_status: KNOWN_PRESENT
      evidence: "E-SHOP-IDOR-DELETE-001-01 now passes"
  lessons_learned:
    - "Destructive operations need explicit ownership checks"
    - "Copy-paste of endpoints should trigger auth review"
    - "Centralized auth middleware prevents omission"
  recommendations:
    - "Require ownership decorator for all CRUD operations"
    - "Add pre-commit hook for auth decorator linting"
 
related_invariants:
  - INV-SHOP-OWNER-DELETE
  - INV-SHOP-AUTH-REQUIRED
 
status: COMPLETE
created_at: "2024-01-14T10:00:00Z"
completed_at: "2024-01-16T09:00:00Z"