In February, KrebsOnSecurity wrote about a novel cybercrime service that helped attackers intercept the one-time passwords (OTPs) that many websites require as a second authentication factor in addition to passwords. That service quickly went offline, but new research reveals a number of competitors have since launched bot-based services that make it relatively easy for crooks to phish OTPs from targets.
Many websites now require users to supply both a password and a numeric code/OTP token sent via text message, or one generated by mobile apps like Authy and Google Authenticator. The idea is that even if the user’s password gets stolen, the attacker still can’t access the user’s account without that second factor — i.e. without access to the victim’s mobile device or phone number.