Marquis, a software vendor that provides communication platforms for financial institutions, disclosed that more than 670,000 customers were impacted by a data breach that occurred in August. The company serves banks, credit unions and other financial institutions with software that facilitates customer communications.
The breach affected at least 74 financial institutions that use Marquis's services, according to the company's November warning to clients. The significantly expanded victim count suggests the initial assessment underestimated the breach's scope by a substantial margin.