System and method for creating heuristic rules based on received email messages to identity business email compromise attacks

Abstract

A method creating a heuristic rule to identify Business Email Compromise (BEC) attacks includes filtering text of received email messages, using a first classifier, to extract one or more terms indicative of a BEC attack from the text of the received email messages, wherein the first classifier includes a trained recurrent neural network that includes a language model, generating, using the first classifier, one or more n-grams based on the extracted terms, wherein each of the n-grams characterizes a particular extracted term, generating, using a second classifier, a vector representation of the extracted terms based on the generated n-grams, assigning a weight coefficient to each of the extracted terms, wherein a higher weight coefficient indicates higher relevancy to BEC attack of the corresponding extracted term, and generating a heuristic rule associated with the BEC attack by combining the weight coefficients of a combination of the extracted terms.