Misrepresentation mail detection apparatus and a cyber attack detection system, and a computer program and misrepresentation mail detection method

摘要

PROBLEM TO BE SOLVED: To determine whether or not a determined mail is possibly a spoofing mail, based on whether or not the determined mail is a via foreign mail.;SOLUTION: When a country to which an E-mail author domain belongs is same as a destination country to which a destination domain of the E-mail belongs, a via foreign mail determination unit 251 determines whether or not the E-mail is sent via a country different from the destination country. A domestic trust domain learning unit 252 counts the number of via foreign mails sent via a country different from the destination country, out of one or more E-mails where the author domain is same as the determined mail. When the determined mail is sent via a country different from the destination country, and the number of via foreign mails is smaller than a predetermined via foreign threshold, a spoofing determination unit 28 determines that the determined mail is possibly a spoofing mail where the author is spoofed.;COPYRIGHT: (C)2014,JPO&INPIT