{
  "family": "ammyy",
  "sample_count": 2,
  "category": "ransomware",
  "description": "Ammyy (classified in antivirus detection telemetry under designations including Ransom:Win32/Ammyy, Ransom.Win32.Ammyy, and Win32/Ammyy) 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, Ammyy 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/Ammyy",
    "Ransom.Win32.Ammyy",
    "Win32/Ammyy"
  ],
  "enrichment_level": "curated_sourced",
  "faq": [
    {
      "@type": "Question",
      "name": "What is Ransom:Win32/Ammyy?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Ammyy is a ransomware threat designed to infiltrate Windows systems and execute unauthorized operations without user consent."
      }
    },
    {
      "@type": "Question",
      "name": "How does Ammyy 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 Ammyy 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 Ammyy 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 Ammyy?",
      "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": "2026-10-16",
  "mitre_attack_detail": [
    {
      "id": "T1219",
      "name": "Remote Access Software (Abusing a legitimate tool for malicious interactive access)",
      "tactic": "Command and Control"
    },
    {
      "id": "T1566.002",
      "name": "Phishing: Spearphishing Link (Social engineering to force the user to download the tool)",
      "tactic": "Initial Access"
    },
    {
      "id": "T1105",
      "name": "Ingress Tool Transfer (Using the Ammyy file manager to drop ransomware)",
      "tactic": "Command and Control"
    }
  ],
  "containment_steps": [
    "Terminate the Ammyy Admin process immediately and isolate the machine to cut off the attacker's interactive session.",
    "If the user was socially engineered into installing it, assume all credentials typed on that machine are compromised and reset them.",
    "Block access to `ammyy.com` and its associated routing IPs at the enterprise perimeter firewall/proxy.",
    "Use EDR to hunt for instances of `AA_*.exe` across the entire environment to ensure it hasn't been deployed laterally."
  ],
  "what_to_avoid": [
    "Do not whitelist Ammyy Admin in your EDR/AV simply because it is a 'legitimate' tool; unless it is officially sanctioned by your IT department, it should be blocked.",
    "Avoid leaving the machine on the network while investigating, as the attacker has live, interactive control."
  ],
  "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/Ammyy",
      "url": "https://www.microsoft.com/en-us/wdsi/threats/malware-encyclopedia-description?Name=Ransom:Win32/Ammyy"
    },
    {
      "name": "Kaspersky Threat Intelligence - Ransom.Win32.Ammyy",
      "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"
  ]
}