{
  "family": "powerun",
  "sample_count": 1,
  "category": "ransomware",
  "description": "<h3>Executive Summary</h3>\nPowerun (often detected as HackTool.Powerun, Riskware.PowerShell, or Trojan.Powerun) is not a standalone malware family, but rather a detection signature for malicious wrappers or execution utilities designed to covertly run PowerShell scripts. Threat actors use Powerun utilities to bypass local execution policies, obfuscate their malicious PowerShell payloads, and execute fileless attacks that evade traditional antivirus scanning.\n\n<h3>Technical Architecture and Exploitation</h3>\nPowerShell is a highly powerful, legitimate administrative framework built into Windows. Because it is a trusted tool, attackers heavily favor it for \"Living off the Land\" (LotL) attacks.\n\nThe \"Powerun\" classification typically applies to utilities that facilitate this abuse:\n<ul>\n<li><strong>Execution Policy Bypass:</strong> By default, Windows restricts the execution of unsigned PowerShell scripts. Powerun tools often execute PowerShell using the `-ExecutionPolicy Bypass` flag or instantiate the PowerShell runspace directly within a custom C# or C++ executable to completely ignore local Group Policy restrictions.</li>\n<li><strong>Obfuscation and Fileless Execution:</strong> Powerun wrappers frequently decode heavily obfuscated (Base64) PowerShell scripts and execute them directly in memory (`-EncodedCommand`). This means the actual malicious payload never touches the hard drive, rendering static disk scanning ineffective.</li>\n<li><strong>AMSI Evasion:</strong> Advanced Powerun utilities attempt to patch or disable the Anti-Malware Scan Interface (AMSI) in memory before executing the PowerShell script, blinding the EDR solution to the script's contents.</li>\n</ul>\n\n<h3>Threat Impact</h3>\nA Powerun detection is a critical indicator of compromise. It signifies that an attacker is actively attempting to execute arbitrary code on the system utilizing trusted system binaries. The payloads executed via Powerun are frequently Cobalt Strike beacons, Empire agents, or ransomware stagers.\n\n<h3>Defense and Resilience Strategies</h3>\n<ul>\n<li><strong>Constrained Language Mode (CLM):</strong> The most effective defense against malicious PowerShell usage is enforcing Constrained Language Mode via Windows Defender Application Control (WDAC). CLM severely restricts the APIs and COM objects that PowerShell can access, neutralizing most offensive scripts.</li>\n<li><strong>Script Block Logging:</strong> Enable PowerShell Script Block Logging (Event ID 4104). This forces the OS to log the *de-obfuscated* content of the script as it executes, providing invaluable telemetry for incident responders.</li>\n<li><strong>Behavioral Monitoring:</strong> Monitor EDR telemetry for suspicious parent-child process relationships, such as Word (`winword.exe`) or Excel (`excel.exe`) unexpectedly spawning `powershell.exe` with encoded command-line arguments.</li>\n</ul>",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [
    "HackTool.Powerun",
    "Riskware.PowerShellRunner",
    "Trojan.Powerun"
  ],
  "enrichment_level": "expert-seo",
  "faq": [
    {
      "@type": "Question",
      "name": "What is Powerun and what threat category does it belong to?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Powerun 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 Powerun establish persistence and evade defensive controls?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Powerun 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 Powerun compromise?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Security teams responding to Powerun 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 HackTool.Powerun employ during execution?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "HackTool.Powerun 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 HackTool.Powerun, and what is the recommended recovery procedure?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Decryption availability for HackTool.Powerun 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": [
    "T1059.001",
    "T1222.001",
    "T1562.001"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-10-15",
  "type": "HackTool / Riskware",
  "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,
  "mitre_attack_detail": [
    {
      "id": "T1059.001",
      "name": "Command and Scripting Interpreter: PowerShell (Used in infection chain)",
      "tactic": "Execution"
    },
    {
      "id": "T1222.001",
      "name": "Windows DACL Modification",
      "tactic": "Defense Evasion"
    },
    {
      "id": "T1562.001",
      "name": "Impair Defenses: Disable or Modify Tools",
      "tactic": "Defense Evasion"
    }
  ],
  "containment_steps": [
    "Immediately isolate affected host(s) from the internal network (disconnect physical Ethernet and disable Wi-Fi/Bluetooth) to prevent Powerun from spreading laterally or encrypting network-attached storage (NAS) and shared SMB volumes.",
    "Preserve volatile system memory (RAM capture) on a representative endpoint before attempting a reboot or power-down, as Powerun symmetric encryption keys or uncompiled payload components may still reside in memory.",
    "Audit process execution logs and terminate active scripting interpreters (e.g. PowerShell, CMD, WScript) or commands executing 'vssadmin.exe delete shadows' or 'wbadmin' used by Powerun to inhibit recovery.",
    "Investigate the initial compromise vector (such as exposed RDP instances, spearphishing attachments, or vulnerable edge gateways) and enforce an immediate credential reset for all compromised Active Directory accounts.",
    "Restore critical assets and databases exclusively from verified, air-gapped, or immutable offline backups once the Powerun binary and related persistence hooks are eradicated."
  ],
  "what_to_avoid": [
    "Do not restart or power cycle infected systems prematurely; doing so destroys volatile RAM encryption keys and may trigger bootloader locking logic embedded in Powerun.",
    "Avoid negotiating or paying the extortion demand without prior forensic evaluation and consultation with incident response specialists, as payment does not guarantee data recovery.",
    "Do not connect clean backup drives or external storage to the affected network until Powerun eradication is completely verified."
  ],
  "target_platforms": [
    "Windows 11",
    "Windows 10",
    "Windows Server 2022",
    "Windows Server 2019"
  ]
}