Cyber criminals have learned how to bypass most of the transaction confirmation processes used in online banking systems. The most popular security features of online banking services are TAN codes with digital signatures. Mobile ZeuS, or Trojan-Spy.*Zitmo, was designed for one sole purpose: to steal mTAN codes without mobile users noticing. ZitMo is still still being used in the same way to steal personal data for online banking and spread in the system. Users were told that the data was requested for the alleged purpose of certificate updates.”]
Source: https://securelist.com/zeus-in-the-mobile-facts-and-theories/36424/