A system including at least one processor; and at least one memory having stored thereon computer program code that, when executed by the at least one processor, controls the at least one processor to: receive an email addressed to a user; separate the email into a plurality of email components; analyze, using respective machine-learning techniques, each of the plurality of email components; feed the analysis of each of the plurality of email components into a stacked ensemble analyzer; and based on an output of the stacked ensemble analyzer, determine whether the email is malicious.