Cisco Talos has observed a threat actor deploying a previously unidentified botnet program Talos is calling “Horabot,” which delivers a known banking trojan and spam tool onto victim machines in a campaign that has been ongoing since at least November 2020. The threat actor appears to be targeting Spanish-speaking users in the Americas and, based on Talos’ analysis, may be located in Brazil.
Horabot enables the threat actor to control the victim’s Outlook mailbox, exfiltrate contacts’ email addresses, and send phishing emails with malicious HTML attachments to all addresses in the victim’s mailbox. The banking trojan can collect the victim’s login credentials for various online accounts, operating system information and keystrokes. It also steals one-time security codes or soft tokens from the victim’s online banking applications. The spam tool compromises Yahoo, Gmail and Outlook webmail accounts, enabling the threat actor to take control of those mailboxes, exfiltrate their contacts’ email addresses, and send spam emails.