{
  "family": "multibanker",
  "sample_count": 1,
  "category": "trojan",
  "description": "Trojan:Win32/Multibanker represents a sophisticated class of financial malware designed to target multiple banking institutions simultaneously. Unlike older, single-target trojans, Multibanker utilizes dynamic configuration files pulled from a Command-and-Control (C2) server, allowing it to adapt its web injects and credential-stealing routines to intercept login attempts across dozens of different online banking portals (`T1185`).<br><br><b>Understanding Multibanker (Financial Fraud)</b><br>To an end-user, the infection is entirely invisible. They will navigate to their legitimate bank website, log in as usual, but the trojan silently intercepts and modifies the transaction in the background. For financial institutions, Multibanker represents a severe threat, as it frequently bypasses standard Two-Factor Authentication (2FA) by tricking the user into entering their OTP into a fake web form injected by the malware.<br><br><b>Execution and Web Injection Mechanics</b><br>Multibanker is typically distributed via malspam (weaponized Office documents) or exploit kits. Upon execution, it establishes persistence (often via Registry Run keys) and injects itself into browser processes (`chrome.exe`, `firefox.exe`, `iexplore.exe`) (`T1055`). It then intercepts API calls related to network traffic (like `HttpSendRequest`). When the user navigates to a targeted bank, Multibanker uses 'Web Injects' (`T1185`) to alter the HTML of the webpage in real-time, inserting extra fields asking for credit card numbers, ATM PINs, or OTPs, which are immediately exfiltrated to the attacker (`T1041`).<br><br><b>Indicators of Compromise & Impact</b><br>The impact is direct financial fraud and total credential compromise. Host-based IoCs include EDR alerts for process injection (specifically into browser processes), unexpected network connections from legitimate browsers to unknown IP addresses (the C2 server fetching the inject configurations), and the presence of hidden, encrypted configuration files in `%AppData%`. Network IoCs involve the browser making encrypted POST requests to the C2 server containing the stolen credentials.",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [],
  "enrichment_level": "expert-seo",
  "faq": [],
  "faq_count": 0,
  "mitre_attack": [
    "T1185",
    "T1041",
    "T1055"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-06-09",
  "mitre_attack_detail": [
    {
      "id": "T1185",
      "name": "Browser Session Hijacking (Using web injects to modify banking portals and steal credentials)",
      "tactic": "Collection"
    },
    {
      "id": "T1055",
      "name": "Process Injection (Injecting into web browsers to monitor traffic)",
      "tactic": "Defense Evasion"
    },
    {
      "id": "T1041",
      "name": "Exfiltration Over C2 Channel (Sending stolen credentials and OTPs to the attacker)",
      "tactic": "Exfiltration"
    }
  ],
  "containment_steps": [
    "Isolate the endpoint immediately to prevent further credential exfiltration and unauthorized transactions.",
    "Assume all credentials stored in or used via web browsers on the infected machine have been compromised.",
    "Contact financial institutions immediately to freeze accounts, report the compromise, and monitor for fraudulent transactions.",
    "Capture a memory dump before remediation to extract the active web inject configurations and identify the targeted banks."
  ],
  "what_to_avoid": [
    "Do not assume that changing the password will stop the fraud; if the malware is still active, it will simply steal the new password and any new OTPs.",
    "Avoid logging into any secure portals (banks, email, corporate VPN) from the infected machine until it has been completely wiped."
  ],
  "target_industries": [
    "Global / Opportunistic"
  ],
  "motivation": "Opportunistic",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ]
}