The banking trojan -- a type of malware used to steal credentials for bank accounts -- has been a staple of cyberthieves for years. However, ransomware, which has proven both easy to use and highly successful, has started eroding its popularity. In a typical banking trojan attack, a robber mounts a phishing campaign to entice a target to open an attachment or click on a link that delivers the malware to the victim's computer. The thief then leverages it to obtain banking credentials and make withdrawals from the mark's account.