What is Illegal Money Remittance?
Illegal money remittance refers to a criminal activity where online banking is exploited to carry out unauthorized transactions without the legitimate user's consent. According to a report by the National Police Agency of Japan, incidents of illegal money remittance surged starting in 2013, reaching 1,495 cases with a total loss of 3.073 billion yen in 2015. While initially, only urban and regional banks were affected, by 2014, the impact spread to credit unions and cooperatives, and by 2015, it extended to agricultural and labor banks as well.
Previously, phishing scams—where victims are directed to fake banking websites resembling legitimate ones to steal their login credentials—were the most common form of this crime. However, a more sophisticated method called MITB (Man-In-The-Browser) has become widespread in recent years.
MITB attacks are triggered by Trojan malware infections. Once installed, the malware resides in the user's web browser and communicates with the attacker's command-and-control (C&C) server to retrieve information, such as a target list of online banking sites. The malware then monitors the user's browsing activity, automatically detecting when the user accesses a targeted banking site. It deceives the user with fake login screens to collect their credentials and uses this information to execute illegal remittance transactions without the user's knowledge. Since the user is interacting with a legitimate banking site, verifying the site's authenticity through server certificates is ineffective. Furthermore, because the unauthorized actions occur after the user logs in, even enhanced authentication methods like one-time passwords offer little protection. Tools to carry out such attacks are easily available, and the range of targeted services is expanding beyond online banking to other platforms.