{
  "family": "trojanbanker",
  "sample_count": 2,
  "category": "ransomware",
  "description": "Trojan:Win32/TrojanBanker is a broad classification encompassing some of the most sophisticated and financially damaging malware in existence (including families like Zeus, Trickbot, Dridex, and Qakbot). Its primary objective is the theft of financial credentials, session cookies, and the manipulation of online banking sessions to facilitate fraudulent wire transfers (`T1111`).<br><br><b>Understanding TrojanBanker (Banking Trojans)</b><br>To an end-user, the infection is highly stealthy. They may log into their bank normally, unaware that the Trojan is manipulating the web page in real-time. For a SOC, a Banking Trojan infection is a critical incident. These trojans have evolved beyond simple keyloggers; they are modular cybercrime platforms. If a Banking Trojan is present on a corporate network, it is highly likely that network will soon be hit with ransomware, as the trojan operators sell access to ransomware cartels.<br><br><b>Execution and Fraud Mechanics</b><br>Distribution is heavily reliant on massive spear-phishing campaigns (`T1566.001`). Once executing, the TrojanBanker establishes deep persistence and injects itself into web browser processes (`T1055`). It uses techniques like 'Man-in-the-Browser' (MitB) to perform web injects (`T1111`): when the user navigates to a targeted banking site, the trojan intercepts the traffic, seamlessly injecting fake HTML forms (asking for 2FA tokens or credit card numbers) into the legitimate banking page. It captures all input before it is encrypted via SSL. Advanced variants also feature hidden VNC modules (`T1071.001`), allowing the attacker to initiate fraudulent transfers directly from the victim's machine to bypass geographic and device-fingerprinting fraud controls.<br><br><b>Indicators of Compromise & Impact</b><br>The impact is direct financial theft and extreme risk of follow-on ransomware. Host-based IoCs include EDR alerts for process hollowing (especially targeting `explorer.exe` or `svchost.exe`), unauthorized API hooking in browser processes (Chrome, Edge, Firefox), and the presence of encrypted configuration files in `%AppData%`. Network IoCs include encrypted beaconing to known C2 infrastructure (often bulletproof hosting) and the download of dynamic web-inject configuration files.",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [],
  "enrichment_level": "expert-seo",
  "faq": [
    {
      "@type": "Question",
      "name": "What is Trojanbanker and what threat category does it belong to?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Trojanbanker is classified as a Ransomware. Documented across security telemetry, it is engineered to execute unauthorized operations, establish persistent footholds on target endpoints, and facilitate malicious campaigns targeting enterprise and individual environments."
      }
    },
    {
      "@type": "Question",
      "name": "How does Trojanbanker establish persistence and evade defensive controls?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Trojanbanker typically establishes persistence through registry run keys, scheduled tasks, or service installations, while evading signature-based antivirus solutions through code obfuscation, memory injection, or anti-analysis sandbox checks."
      }
    },
    {
      "@type": "Question",
      "name": "What are the essential incident response steps for mitigating a Trojanbanker compromise?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Security teams responding to Trojanbanker should immediately isolate affected endpoints from the network, perform memory triage to capture volatile forensic artifacts, audit registry and startup persistence mechanisms, revoke exposed user credentials, and restore systems from verified, clean backups."
      }
    },
    {
      "@type": "Question",
      "name": "What cryptographic algorithms and file targeting techniques does Trojanbanker employ during execution?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Trojanbanker typically leverages hybrid cryptographic architectures combining symmetric stream or block ciphers (such as AES-256 or ChaCha20) for rapid file encryption with asymmetric algorithms (such as RSA-2048 or Curve25519) to securely protect the session keys. It aggressively targets sensitive file extensions including corporate documents, databases, virtual disks, and backups while systematically executing commands to delete Volume Shadow Copies (vssadmin delete shadows /all /quiet) and disable system recovery options."
      }
    },
    {
      "@type": "Question",
      "name": "Are decryptors available for Trojanbanker, and what is the recommended recovery procedure?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Decryption availability for Trojanbanker depends on whether security researchers or law enforcement (such as the No More Ransom initiative) have recovered the master private keys or discovered flaws in its key generation routines. Victims should never pay the extortion demand, as payment fuels criminal operations without guaranteeing file restoration. The recommended recovery procedure entails isolating infected hosts, conducting forensic disk imaging, identifying the root access vector, and restoring validated systems from immutable offline backups."
      }
    }
  ],
  "faq_count": 5,
  "mitre_attack": [
    "T1056.001",
    "T1566.001",
    "T1055",
    "T1111"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-06-09",
  "mitre_attack_detail": [
    {
      "id": "T1111",
      "name": "Two-Factor Authentication Interception (Using Man-in-the-Browser web injects to steal OTPs)",
      "tactic": "Credential Access"
    },
    {
      "id": "T1056.001",
      "name": "Input Capture: Keylogging (Capturing credentials during login)",
      "tactic": "Credential Access"
    },
    {
      "id": "T1055",
      "name": "Process Injection (Injecting into web browsers to monitor traffic)",
      "tactic": "Defense Evasion"
    },
    {
      "id": "T1566.001",
      "name": "Phishing: Spearphishing Attachment (Primary delivery mechanism)",
      "tactic": "Initial Access"
    }
  ],
  "containment_steps": [
    "Isolate the infected endpoint IMMEDIATELY. Banking trojans are a primary precursor to enterprise ransomware deployment.",
    "Initiate a forced password reset for ALL accounts accessed from the infected machine, especially corporate banking and VPN credentials.",
    "Capture a live memory image (RAM dump) to extract the decrypted banking trojan modules, C2 lists, and targeted bank inject configurations.",
    "Notify the organization's financial institution to place holds or monitoring on accounts that may have been compromised."
  ],
  "what_to_avoid": [
    "Do not allow the user to log into ANY accounts while the machine is connected to the network, as the Man-in-the-Browser capability is active.",
    "Avoid treating this as a minor malware infection; the presence of a banking trojan indicates a severe, high-tier compromise."
  ],
  "target_industries": [
    "Healthcare",
    "Critical Infrastructure",
    "Enterprise"
  ],
  "motivation": "Financial Extortion",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ],
  "attack_stage": [
    "defense_evasion",
    "impact"
  ],
  "ecosystem": [
    "windows_pe"
  ],
  "is_emerging": false,
  "target_platforms": [
    "Windows 11",
    "Windows 10",
    "Windows Server 2022",
    "Windows Server 2019"
  ]
}