{
  "family": "rantest",
  "sample_count": 5,
  "category": "ransomware",
  "description": "Ransom:Win32/Rantest is generally a heuristic classification for a test file, a proof-of-concept (PoC), or a benign simulator designed to mimic the behavior of destructive ransomware. It is frequently used by security vendors, SOC analysts, and penetration testers to safely evaluate the efficacy of Endpoint Detection and Response (EDR) solutions and behavioral blockers without risking actual data loss.<br><br><b>Understanding Ransomware Simulators</b><br>To an end-user, a Rantest file might generate a scary antivirus alert, but it will not actually encrypt their files. For a SOC analyst, a Rantest detection is usually a benign true positive—the security tool correctly identified ransomware-like behavior (e.g., rapid file enumeration and modification), but the intent of the software was testing, not extortion. However, analysts must always verify the origin of the file to ensure it is not a novel, fully weaponized threat misclassified as a test.<br><br><b>Execution and Simulated Extortion Mechanics</b><br>Rantest files are executed intentionally by security personnel (`T1204.002`). Upon execution, the simulator will mimic the kill chain of modern ransomware. It may execute commands like `vssadmin.exe delete shadows` to test if the EDR blocks shadow copy deletion (`T1490`). It will then rapidly iterate through a designated test directory, opening files, reading the contents, encrypting them in memory, and writing them back to disk with a new extension (like `.test`) (`T1486`). A high-quality simulator will also attempt to mimic the process hollowing or injection techniques (`T1055`) used by real ransomware to evade initial detection, providing a comprehensive test of the endpoint's behavioral analysis engine.<br><br><b>Indicators of Compromise & Impact</b><br>The impact should be zero (if run in a controlled test environment). Host-based IoCs mirror actual ransomware: spikes in CPU and disk I/O, rapid file renaming, and EDR alerts for mass file modification. The critical difference is the context of execution (run by a known administrator in a test folder) and the ability to cleanly reverse the encryption.",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [],
  "enrichment_level": "expert-seo",
  "faq": [
    {
      "@type": "Question",
      "name": "What is Rantest and what threat category does it belong to?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Rantest is classified as a Ransomware. Documented across security telemetry, it is engineered to execute unauthorized operations, establish persistent footholds on target endpoints, and facilitate malicious campaigns targeting enterprise and individual environments."
      }
    },
    {
      "@type": "Question",
      "name": "How does Rantest establish persistence and evade defensive controls?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Rantest typically establishes persistence through registry run keys, scheduled tasks, or service installations, while evading signature-based antivirus solutions through code obfuscation, memory injection, or anti-analysis sandbox checks."
      }
    },
    {
      "@type": "Question",
      "name": "What are the essential incident response steps for mitigating a Rantest compromise?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Security teams responding to Rantest should immediately isolate affected endpoints from the network, perform memory triage to capture volatile forensic artifacts, audit registry and startup persistence mechanisms, revoke exposed user credentials, and restore systems from verified, clean backups."
      }
    },
    {
      "@type": "Question",
      "name": "What cryptographic algorithms and file targeting techniques does Rantest employ during execution?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Rantest typically leverages hybrid cryptographic architectures combining symmetric stream or block ciphers (such as AES-256 or ChaCha20) for rapid file encryption with asymmetric algorithms (such as RSA-2048 or Curve25519) to securely protect the session keys. It aggressively targets sensitive file extensions including corporate documents, databases, virtual disks, and backups while systematically executing commands to delete Volume Shadow Copies (vssadmin delete shadows /all /quiet) and disable system recovery options."
      }
    },
    {
      "@type": "Question",
      "name": "Are decryptors available for Rantest, and what is the recommended recovery procedure?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Decryption availability for Rantest depends on whether security researchers or law enforcement (such as the No More Ransom initiative) have recovered the master private keys or discovered flaws in its key generation routines. Victims should never pay the extortion demand, as payment fuels criminal operations without guaranteeing file restoration. The recommended recovery procedure entails isolating infected hosts, conducting forensic disk imaging, identifying the root access vector, and restoring validated systems from immutable offline backups."
      }
    }
  ],
  "faq_count": 5,
  "mitre_attack": [
    "T1486",
    "T1490",
    "T1055"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-06-09",
  "mitre_attack_detail": [
    {
      "id": "T1486",
      "name": "Data Encrypted for Impact (Simulated)",
      "tactic": "Impact"
    },
    {
      "id": "T1490",
      "name": "Inhibit System Recovery (Simulated Shadow Copy Deletion)",
      "tactic": "Impact"
    },
    {
      "id": "T1055",
      "name": "Process Injection (Simulated Evasion)",
      "tactic": "Defense Evasion"
    }
  ],
  "containment_steps": [
    "Verify the context of the alert; if the executable was run by a member of the security team during an authorized test, log the EDR's successful block or detection and close the incident.",
    "If the alert triggered on a standard user's workstation without authorization, treat it as a potential live ransomware incident until proven otherwise.",
    "Isolate the machine and capture the executable for static analysis to confirm it is a benign simulator (like KnowBe4's RanSim) and not a live variant of Conti or LockBit.",
    "Review the EDR telemetry to ensure the simulator did not actually modify critical user data outside of the designated test boundaries."
  ],
  "what_to_avoid": [
    "Do not ignore the alert simply because it contains 'test' in the name; threat actors occasionally name their malware benignly to trick analysts.",
    "Avoid running ransomware simulators on production endpoints without explicit authorization and a fully tested backup recovery plan."
  ],
  "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,
  "target_platforms": [
    "Windows 11",
    "Windows 10",
    "Windows Server 2022",
    "Windows Server 2019"
  ]
}