InvoiceShelf is an open-source web & mobile app that helps track expenses, payments and create professional invoices and estimates. Prior to version 2.4.0, POST /api/v1/estimates/{estimate}/convert-to-invoice in ConvertEstimateController authorizes only the caller's create-invoice ability and does not authorize access to the route-bound Estimate. Because route-model binding can resolve an estimate from any company, an authenticated user with create-invoice ability can copy another company's line items, prices, totals, taxes, notes, currency, and customer data into an invoice in the attacker's