{
  "family": "vtub",
  "sample_count": 1,
  "category": "advanced_threat",
  "description": "<h3>Executive Summary</h3>\nVtub is a malicious network worm designed to propagate rapidly across local area networks (LANs) and removable media. While it frequently serves as a \"dropper\" for secondary payloads (such as botnet agents or adware), its primary function is self-replication. Vtub relies on exploiting weak network configurations and legacy Windows features to achieve maximum saturation within a target environment.\n\n<h3>Propagation and Execution Lifecycle</h3>\nVtub utilizes a multi-pronged approach to maximize its infection radius within an organization.\n\nIts execution lifecycle relies on exploiting network trust:\n<ul>\n<li><strong>Network Share Exploitation:</strong> Vtub aggressively scans the local network for open Server Message Block (SMB) network shares. It attempts to brute-force weak administrator credentials or exploit misconfigured permissions to silently copy its executable to adjacent servers and workstations.</li>\n<li><strong>Removable Media Propagation:</strong> The worm actively monitors the system for newly inserted USB flash drives. When a drive is detected, it copies itself to the root directory and creates a malicious `AutoRun.inf` file to ensure it executes automatically when the drive is inserted into a new machine.</li>\n<li><strong>Persistence and Modification:</strong> Once active on a host, Vtub modifies the Windows Registry (e.g., adding entries to the `Run` key) to establish persistence. It frequently alters system policies to disable Task Manager and Registry Editor, hindering manual removal and analysis.</li>\n</ul>\n\n<h3>Threat Assessment</h3>\nA Vtub infection is highly disruptive. Because of its aggressive worm capabilities, a single infected endpoint can lead to the rapid infection of hundreds of machines across the enterprise, causing network congestion. The ability of the worm to act as a dropper for secondary, more severe malware elevates this to a high-risk security event.\n\n<h3>Eradication and Incident Response</h3>\n<ul>\n<li><strong>Immediate Network Segmentation:</strong> Do not just isolate the initially infected machine. Physically or logically segment the affected VLAN to halt the lateral spread of the worm via open SMB shares.</li>\n<li><strong>Disable AutoRun/AutoPlay:</strong> Enforce strict Group Policy Objects (GPOs) that entirely disable AutoRun and AutoPlay functionality across all drives in the enterprise to prevent the USB propagation vector.</li>\n<li><strong>Enterprise-Wide Sweeps:</strong> Conduct a massive forensic sweep across all endpoints and network shares to identify the Vtub executable, remove its persistence mechanisms, and repair the damaged registry keys (restoring access to Task Manager).</li>\n</ul>",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [
    "Worm.Vtub",
    "W32/Vtub",
    "NetWorm.Vtub"
  ],
  "enrichment_level": "insufficient_information",
  "faq": [],
  "faq_count": 0,
  "mitre_attack": [
    "T1091",
    "T1547.001",
    "T1564.001",
    "T1059"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-07-01T17:04:40Z",
  "type": "Worm",
  "target_industries": [
    "Global / Opportunistic"
  ],
  "motivation": "Opportunistic",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ]
}