Banking industry giant NCR Corp. [NYSE: NCR] late last month took the unusual step of temporarily blocking third-party financial data aggregators Mint and QuickBooks Online from accessing Digital Insight, an online banking platform used by hundreds of financial institutions. That ban, which came in response to a series of bank account takeovers in which cybercriminals used aggregation sites to surveil and drain consumer accounts, has since been rescinded. But the incident raises fresh questions about the proper role of digital banking platforms in fighting password abuse.