{
  "family": "vanilloader",
  "sample_count": 6,
  "category": "ransomware",
  "description": "TrojanDownloader:Win32/Vanilloader is a lightweight, highly obfuscated trojan designed exclusively to act as the first stage in a multi-stage infection chain. Its sole purpose is to securely bypass initial endpoint defenses, establish a foothold, and silently download and execute a much more destructive secondary payload, such as a banking trojan, ransomware, or an advanced infostealer.<br><br><b>Understanding the Downloader Threat</b><br>To an end-user, Vanilloader is entirely invisible. It does not display ransom notes or steal data itself. For a security analyst, Vanilloader is a critical 'Initial Access' indicator. If Vanilloader is detected on a system, it means the perimeter has been breached, and the immediate priority is determining whether it successfully downloaded its secondary payload before being quarantined.<br><br><b>Execution and Delivery Mechanics</b><br>Vanilloader is typically distributed via spear-phishing campaigns (`T1566.001`) containing malicious Office documents (using VBA macros) or zipped executables disguised as invoices. Upon execution (`T1204.002`), the trojan employs anti-analysis techniques to check if it is running in a sandbox (`T1497`). It then connects to a hardcoded, often compromised, Command-and-Control (C2) server (`T1071.001`). It requests the secondary payload, often downloading it directly into system memory (`T1055`) or saving it to the `%Temp%` directory under a randomized name before executing it (`T1105`). Once the secondary payload is running, Vanilloader frequently deletes itself to remove forensic evidence.<br><br><b>Indicators of Compromise & Impact</b><br>The primary impact is the successful deployment of a high-severity threat. Host-based IoCs include EDR alerts for office applications (e.g., `WINWORD.EXE`) spawning anomalous child processes (like `powershell.exe` or `cmd.exe`) which then reach out to the internet. Network IoCs include a sudden, short burst of outbound HTTP/HTTPS traffic to an unknown, low-reputation IP address, followed immediately by the download of an executable payload or encrypted blob.",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [],
  "enrichment_level": "expert-seo",
  "faq": [],
  "faq_count": 0,
  "mitre_attack": [
    "T1204.002",
    "T1566.001",
    "T1105",
    "T1055"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-06-09",
  "mitre_attack_detail": [
    {
      "id": "T1105",
      "name": "Ingress Tool Transfer (Downloading the secondary payload)",
      "tactic": "Command and Control"
    },
    {
      "id": "T1566.001",
      "name": "Phishing: Spearphishing Attachment",
      "tactic": "Initial Access"
    },
    {
      "id": "T1204.002",
      "name": "User Execution: Malicious File",
      "tactic": "Execution"
    },
    {
      "id": "T1055",
      "name": "Process Injection (Executing payload in memory)",
      "tactic": "Defense Evasion"
    }
  ],
  "containment_steps": [
    "Immediately isolate the endpoint from the network to sever the C2 connection and prevent the secondary payload from executing or exfiltrating data.",
    "Do not assume the threat is neutralized if the AV deleted the Vanilloader executable; you must verify if the secondary payload was successfully downloaded first.",
    "Analyze EDR and proxy logs to identify the C2 domain Vanilloader contacted and block it enterprise-wide.",
    "Identify the specific phishing email that delivered Vanilloader and purge it from all other corporate inboxes to prevent further compromise."
  ],
  "what_to_avoid": [
    "Do not close the incident investigation without definitively identifying the secondary payload (e.g., Trickbot, Emotet); the downloader is just the delivery mechanism.",
    "Avoid relying solely on file hashes for detection, as Vanilloader binaries are frequently re-packed and heavily obfuscated."
  ],
  "target_industries": [
    "Global / Opportunistic"
  ],
  "motivation": "Opportunistic",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ]
}