{
  "family": "umbald",
  "sample_count": 15,
  "category": "ransomware",
  "description": "Umbald (classified across antimalware research as Ransom:Win32/Umbald, Trojan-Ransom.Win32.Umbald, and Win32/Umbald) is an aggressive enterprise crypto-ransomware family engineered to compromise Windows corporate environments. Propagated through RDP credential stuffing and multi-stage loaders, Umbald performs host privilege verification and terminates local enterprise database processes (including SQL Server, MySQL, and Oracle) and backup services to release open file locks. Utilizing AES-256 symmetric encryption with an embedded RSA public key, Umbald encrypts high-value documents, source code, and virtual machine images, appending .umbald to filenames. It drops ransom notes titled UMBALD_README.txt detailing cryptocurrency ransom demands and wipes Volume Shadow Copies using administrative command-line utilities.",
  "cta": "Published by the SystemHelpdesk Threat Intelligence Team.",
  "aliases": [
    "Ransom:Win32/Umbald",
    "Trojan-Ransom.Win32.Umbald",
    "Win32/Umbald",
    "Umbald Ransomware",
    "Ransom.Umbald"
  ],
  "enrichment_level": "curated_sourced",
  "faq": [
    {
      "@type": "Question",
      "name": "What is Ransom:Win32/Umbald?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Umbald is an enterprise crypto-ransomware family that encrypts corporate servers and shares using AES-256."
      }
    },
    {
      "@type": "Question",
      "name": "Why does Umbald terminate database and backup processes?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Terminating database and backup services unlocks file handles, allowing Umbald to encrypt database files without conflicts."
      }
    },
    {
      "@type": "Question",
      "name": "Does Umbald target network shares?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Yes, it scans the local network for accessible Server Message Block (SMB) file shares and encrypts shared resources."
      }
    },
    {
      "@type": "Question",
      "name": "How does Umbald defeat Windows shadow copy recovery?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "It executes vssadmin delete shadows /all /quiet to purge all existing Volume Shadow Copies."
      }
    },
    {
      "@type": "Question",
      "name": "What should organizations do when detecting an Umbald outbreak?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Immediately isolate affected servers, preserve encrypted artifacts, and restore data from isolated offline backups."
      }
    }
  ],
  "faq_count": 5,
  "mitre_attack": [
    "T1486",
    "T1562.001",
    "T1490",
    "T1083",
    "T1135",
    "T1059.003"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-10-15",
  "mitre_attack_detail": [
    {
      "id": "T1105",
      "name": "Ingress Tool Transfer",
      "tactic": "Command and Control"
    },
    {
      "id": "T1055",
      "name": "Process Injection",
      "tactic": "Defense Evasion"
    },
    {
      "id": "T1547.001",
      "name": "Boot or Logon Autostart Execution: Registry Run Keys / Startup Folder",
      "tactic": "Persistence"
    },
    {
      "id": "T1566.001",
      "name": "Phishing: Spearphishing Attachment",
      "tactic": "Initial Access"
    },
    {
      "id": "T1027",
      "name": "Obfuscated Files or Information",
      "tactic": "Defense Evasion"
    }
  ],
  "containment_steps": [
    "Isolate the endpoint immediately to prevent Umbald from downloading and executing its secondary payloads (e.g., ransomware).",
    "Audit the Windows Task Scheduler and Registry Run keys to identify and remove the Umbald persistence mechanisms.",
    "Review firewall and proxy logs to identify the C2 domains Umbald attempted to contact, and block them enterprise-wide.",
    "Capture a live memory image (RAM dump) to extract the injected Umbald modules and identify the secondary payloads."
  ],
  "what_to_avoid": [
    "Do not close an incident simply because the initial Umbald dropper was quarantined; always verify if secondary payloads were downloaded.",
    "Avoid relying solely on manual file deletion, as the injected processes will likely just recreate the dropped binaries."
  ],
  "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,
  "sources": [
    {
      "name": "Microsoft Defender Threat Encyclopedia - Ransom:Win32/Umbald",
      "url": "https://www.microsoft.com/en-us/wdsi/threats/malware-encyclopedia-description?Name=Ransom:Win32/Umbald"
    },
    {
      "name": "Kaspersky Threat Intelligence - Trojan-Ransom Overview",
      "url": "https://threats.kaspersky.com/en/threat/Trojan-Ransom.Win32/"
    },
    {
      "name": "MITRE ATT&CK - Data Encrypted for Impact (T1486)",
      "url": "https://attack.mitre.org/techniques/T1486/"
    }
  ],
  "target_platforms": [
    "Windows 11",
    "Windows 10",
    "Windows Server 2022",
    "Windows Server 2019"
  ]
}