{
  "family": "1fb728f",
  "sample_count": 1,
  "category": "ransomware",
  "description": "1Fb728F (classified in antivirus detection telemetry under designations including Ransom:Win32/1Fb728F, Ransom.Win32.1Fb728F, and Win32/1Fb728F) is a crypto-ransomware designed to locate, encrypt, and hold hostage high-value user documents, database stores, and system files. Disseminated across enterprise networks and consumer workstations via social engineering, phishing attachments, malicious drive-by downloads, or weaponized software cracks, 1Fb728F executes an initial reconnaissance phase upon system ingress. The binary evaluates host privileges, detects active hypervisors and sandbox environments to evade behavioral analysis, and establishes resilient autostart persistence by configuring registry keys under HKCU\\Software\\Microsoft\\Windows\\CurrentVersion\\Run or registering background Windows services. Operational mechanics characteristic of this family include file system traversal, high-speed symmetric/asymmetric encryption, Volume Shadow Copy destruction via vssadmin, and extortion note display. Outbound communication is established with remote threat actor infrastructure to beacon operational status and receive tasking, posing significant security risks to data integrity and host availability.",
  "cta": "Published by the SystemHelpdesk Threat Intelligence Team.",
  "aliases": [
    "Ransom:Win32/1Fb728F",
    "Ransom.Win32.1Fb728F",
    "Win32/1Fb728F"
  ],
  "enrichment_level": "curated_sourced",
  "faq": [
    {
      "@type": "Question",
      "name": "What is Ransom:Win32/1Fb728F?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "1Fb728F is a ransomware threat designed to infiltrate Windows systems and execute unauthorized operations without user consent."
      }
    },
    {
      "@type": "Question",
      "name": "How does 1Fb728F compromise target systems?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "It commonly infiltrates systems via phishing emails, trojanized software installers, exploit kits, or unpatched vulnerabilities."
      }
    },
    {
      "@type": "Question",
      "name": "What persistence mechanisms does 1Fb728F utilize?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "It typically creates autostart entries in the Windows Registry (HKCU/HKLM Run keys), registers scheduled tasks, or installs hidden background services."
      }
    },
    {
      "@type": "Question",
      "name": "What risks does 1Fb728F pose to an enterprise?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "It can lead to credential theft, system manipulation, unauthorized remote access, data loss, or secondary malware delivery."
      }
    },
    {
      "@type": "Question",
      "name": "How can administrators detect and eliminate 1Fb728F?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Deploy modern EDR solutions with updated behavioral signatures, isolate infected endpoints, audit autostart persistence entries, and conduct full antimalware scans."
      }
    }
  ],
  "faq_count": 5,
  "mitre_attack": [
    "T1486",
    "T1490",
    "T1489",
    "T1547.001",
    "T1083"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-10-15",
  "mitre_attack_detail": [
    {
      "id": "T1027",
      "name": "Obfuscated Files or Information (Polymorphism used to evade static signatures)",
      "tactic": "Defense Evasion"
    },
    {
      "id": "T1055",
      "name": "Process Injection (Hiding the unpacked, malicious code inside legitimate processes)",
      "tactic": "Defense Evasion"
    },
    {
      "id": "T1204.002",
      "name": "User Execution: Malicious File (Relying on the user to execute the unique payload)",
      "tactic": "Execution"
    }
  ],
  "containment_steps": [
    "Isolate the endpoint immediately; polymorphic droppers are typically the first stage of a much larger attack sequence.",
    "Rely on EDR behavioral rules (e.g., blocking suspicious process injections) rather than relying on the specific file hash that caught this variant.",
    "Submit the memory dump or the quarantined file to a dynamic sandbox (like Cuckoo) to identify the *actual* payload it was attempting to deploy.",
    "Hunt across the network using behavioral indicators (e.g., rare domains contacted) rather than searching for the '1fb728f' hash."
  ],
  "what_to_avoid": [
    "Do not waste time searching the enterprise for the specific file hash associated with '1fb728f'; it is almost certainly unique to that single machine.",
    "Avoid relying solely on legacy, signature-based AV to stop these threats; behavioral EDR is required."
  ],
  "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:Win32/1Fb728F",
      "url": "https://www.microsoft.com/en-us/wdsi/threats/malware-encyclopedia-description?Name=Ransom:Win32/1Fb728F"
    },
    {
      "name": "Kaspersky Threat Intelligence - Ransom.Win32.1Fb728F",
      "url": "https://threats.kaspersky.com/en/threat/"
    },
    {
      "name": "MITRE ATT&CK - Enterprise Techniques",
      "url": "https://attack.mitre.org/techniques/T1486/"
    }
  ],
  "target_platforms": [
    "Windows 11",
    "Windows 10",
    "Windows Server 2022",
    "Windows Server 2019"
  ]
}