{
  "family": "vbcryptor",
  "sample_count": 3,
  "category": "ransomware",
  "description": "Ransomware:Win32/Vbcryptor is a broad detection name applied to various strains of ransomware, file encoders, and malicious crypters that are compiled using Microsoft Visual Basic (VB) or Visual Basic .NET (VB.NET). Because VB executables are often heavily dependent on the .NET framework and are relatively easy to decompile, malware authors use 'Vbcryptor' wrapper tools to heavily obfuscate their actual payloads, making static analysis extremely difficult.<br><br><b>Understanding Vbcryptor (Visual Basic Crypters)</b><br>To an end-user, an encounter with Vbcryptor usually ends in tragedy: personal files are suddenly appended with strange extensions (like `.locked` or `.crypto`), and a ransom note demands cryptocurrency to restore access. For a malware analyst, encountering a Vbcryptor file means the first step is unpacking. The outer VB layer is rarely the actual ransomware; instead, it is a highly obfuscated 'packer' or 'crypter' designed solely to evade antivirus (`T1027.002`). The true payload (which could be anything from a banking trojan to a well-known ransomware family like Locky or Cerber) is hidden inside, encrypted.<br><br><b>Execution and Unpacking Mechanics</b><br>Vbcryptor variants are distributed via phishing (`T1566.001`), drive-by downloads, or RDP brute-forcing. Upon execution (`T1204.002`), the VB executable loads into memory. It then executes a decryption routine to unpack its hidden payload directly into a hollowed-out process (Process Hollowing - `T1055.012`) like `svchost.exe` or `vbc.exe`. By running the payload exclusively in memory, the malware avoids dropping the true ransomware binary to the disk, bypassing many legacy, signature-based AV scanners. Once the hidden ransomware executes, it begins iterating through local and network drives (`T1083`), encrypting user files (`T1486`).<br><br><b>Indicators of Compromise & Impact</b><br>The impact is catastrophic data loss or severe operational downtime. Host-based IoCs include anomalous child processes spawning from generic Windows executables, mass file modifications (`T1486`), and the dropping of ransom notes (e.g., `DECRYPT_FILES.txt`). Network IoCs may include the payload attempting to communicate with Tor gateways or known C2 infrastructure.",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [],
  "enrichment_level": "expert-seo",
  "faq": [],
  "faq_count": 0,
  "mitre_attack": [
    "T1055.012",
    "T1486",
    "T1027.002",
    "T1083"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-06-09",
  "mitre_attack_detail": [
    {
      "id": "T1486",
      "name": "Data Encrypted for Impact (Ransomware payload)",
      "tactic": "Impact"
    },
    {
      "id": "T1027.002",
      "name": "Obfuscated Files or Information: Software Packing (VB Crypters)",
      "tactic": "Defense Evasion"
    },
    {
      "id": "T1055.012",
      "name": "Process Injection: Process Hollowing",
      "tactic": "Defense Evasion"
    },
    {
      "id": "T1083",
      "name": "File and Directory Discovery",
      "tactic": "Discovery"
    }
  ],
  "containment_steps": [
    "Immediately disconnect the infected endpoint from the network (unplug ethernet, disable Wi-Fi) to stop the ransomware from encrypting shared network drives.",
    "Do not immediately reboot the machine; if the ransomware is currently executing, a reboot might destroy the encryption keys temporarily held in RAM.",
    "Capture a full memory dump; analysts can often extract the unpacked payload and sometimes the encryption keys directly from the hollowed process.",
    "Restore affected files from an offline, verified backup solution."
  ],
  "what_to_avoid": [
    "Do not pay the ransom; paying funds criminal organizations and there is no guarantee the decryptor provided will actually work.",
    "Avoid relying on static AV scans of the original Vbcryptor file; the outer VB shell is often highly polymorphic and changes its hash constantly."
  ],
  "target_industries": [
    "Global / Opportunistic"
  ],
  "motivation": "Opportunistic",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ]
}