{
  "family": "magistrcorr",
  "sample_count": 1,
  "category": "advanced_threat",
  "description": "<h3>Executive Summary</h3>\nMagistrcorr is a heuristic detection applied to variants, remnants, or corrupted (hence \"corr\") versions of the notorious Win32/Magistr family. Magistr is a complex, destructive polymorphic virus and mass-mailing worm that caused widespread damage in the early 2000s. While active outbreaks are rare today on modern operating systems, the detection of a Magistr variant indicates a severe legacy infection or the presence of a highly destructive payload capable of wiping hard drives and destroying BIOS firmware.\n\n<h3>Infection Vector and Technical Capabilities</h3>\nMagistr traditionally spreads by harvesting email addresses from the infected machine's address book (Outlook, Eudora) and mailing itself out with randomly generated subject lines and attachments. It also infects executable files (`.exe`, `.scr`) on local and mapped network drives.\n\nUpon execution, Magistr exhibits highly destructive behavior:\n<ul>\n<li><strong>Polymorphic File Infection:</strong> Magistr infects PE (Portable Executable) files by injecting its code and altering the entry point. It is highly polymorphic, meaning the virus encrypts its own body with a different key for every infected file, making signature-based detection difficult.</li>\n<li><strong>Mass-Mailing and Lateral Movement:</strong> It implements its own SMTP engine to mass-mail copies of infected files to harvested email addresses, utilizing the compromised host to attack external networks and internal peers.</li>\n<li><strong>Destructive Payload (Time Bomb):</strong> The most critical threat is its delayed destructive payload. After a certain period (e.g., one month after initial infection), the virus attempts to overwrite the system's hard drive with garbage data (wiping the MBR and FAT) and attempts to flash (destroy) the motherboard's BIOS firmware, rendering the computer permanently unbootable (similar to the CIH/Chernobyl virus).</li>\n</ul>\n\n<h3>Threat Assessment</h3>\nA Magistr detection is a critical security incident. The malware is exceptionally destructive. Even if the \"corr\" designation implies the file is corrupted and potentially non-functional, it indicates that a highly destructive, self-replicating virus was present on the network.\n\n<h3>Incident Response and Remediation</h3>\n<ul>\n<li><strong>Immediate Isolation (Hard Stop):</strong> Instantly isolate the machine from the network. If the destructive payload is suspected to be active, a hard power-off is recommended to prevent the hard drive from being wiped.</li>\n<li><strong>Forensic Triage:</strong> Boot the machine from a clean, offline environment (e.g., a Linux Live USB) to scan the drive and attempt data recovery before attempting any disinfection.</li>\n<li><strong>Complete System Rebuild:</strong> Because Magistr deeply infects system executables and can damage firmware, attempting to \"clean\" the files is highly unreliable. The machine must be completely wiped, the BIOS flashed with a clean image from the manufacturer, and the OS re-installed from a known-good baseline.</li>\n</ul>",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [
    "Virus.Win32.Magistr",
    "Worm.Magistr",
    "Win32/Magistr.corrupt"
  ],
  "enrichment_level": "expert-seo",
  "faq": [
    {
      "@type": "Question",
      "name": "What is Magistrcorr and what threat category does it belong to?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Magistrcorr is classified as a Advanced Threat. 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 Magistrcorr establish persistence and evade defensive controls?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Magistrcorr 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 Magistrcorr compromise?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Security teams responding to Magistrcorr 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 lateral movement and credential access tactics does Virus.Win32.Magistr leverage in enterprise intrusions?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Virus.Win32.Magistr frequently utilizes privileged account harvesting techniques such as LSASS memory dumping, Kerberoasting, and token impersonation to escalate privileges. Once administrative credentials are acquired, it pivots across the victim network utilizing living-off-the-land binaries (LOLBins) such as WMI, PowerShell remoting, and PsExec, or abuses remote desktop protocols (RDP) to reach critical internal repositories and domain controllers."
      }
    },
    {
      "@type": "Question",
      "name": "How does Virus.Win32.Magistr maintain covert communications and evade perimeter network monitoring?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Virus.Win32.Magistr often relies on multi-stage command and control (C2) architectures utilizing encrypted protocols over standard web ports (HTTPS/443 or DNS tunneling) to blend in with legitimate enterprise network traffic. Many variants incorporate proxy networks, domain fronting, or cloud services (such as Microsoft Graph API, Google Drive, or Telegram) to masquerade C2 channels, bypassing traditional signature-based egress filtering."
      }
    }
  ],
  "faq_count": 5,
  "mitre_attack": [
    "T1485",
    "T1561.002",
    "T1055"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-10-15",
  "type": "Virus / Mass-Mailing Worm (Destructive)",
  "target_industries": [
    "Global / Opportunistic"
  ],
  "motivation": "Opportunistic",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ],
  "attack_stage": [
    "execution",
    "persistence"
  ],
  "ecosystem": [
    "windows_pe"
  ],
  "is_emerging": false,
  "mitre_attack_detail": [
    {
      "id": "T1485",
      "name": "Data Destruction",
      "tactic": "Impact"
    },
    {
      "id": "T1561.002",
      "name": "Disk Wipe: Disk Structure Wipe",
      "tactic": "Impact"
    },
    {
      "id": "T1055",
      "name": "Process Injection",
      "tactic": "Defense Evasion"
    }
  ],
  "containment_steps": [
    "Enforce forensic network isolation on all suspected endpoints while maintaining an out-of-band telemetry conduit to capture live Magistrcorr adversary activity.",
    "Perform full memory dumps across identified staging nodes to extract memory-only implants, kernel rootkit hooks, and decrypted Magistrcorr C2 infrastructure IP/domain lists.",
    "Review Active Directory domain controller authentication logs for anomalous Kerberos ticket requests (Pass-the-Ticket, Golden Ticket) and unauthorized DCSync operations associated with Magistrcorr.",
    "Block all confirmed C2 domains, dynamic DNS endpoints, and proxy IP addresses across perimeter firewalls, proxies, and DNS security gateways.",
    "Conduct an enterprise-wide sweep across surrounding subnets for secondary webshells, WMI event subscriptions, or remote execution tooling left behind by Magistrcorr operators."
  ],
  "what_to_avoid": [
    "Do not assume the incident is resolved simply because an antivirus tool removed the initial Magistrcorr dropper; always verify that secondary payloads and persistence hooks have been eradicated.",
    "Avoid logging in with Domain Admin or privileged credentials on a machine suspected of running Magistrcorr until memory triage is complete.",
    "Do not delay host isolation; automated lateral movement and credential dumping can occur within minutes of initial execution."
  ],
  "target_platforms": [
    "Windows 11",
    "Windows 10",
    "Windows Server 2022",
    "Windows Server 2019"
  ]
}