{
  "family": "nyxem",
  "sample_count": 1,
  "category": "advanced_threat",
  "description": "<h3>Executive Summary</h3>\nNyxem (widely known as Kama Sutra, Blackmal, or MyWife) is a highly destructive mass-mailing computer worm that gained global infamy in early 2006. It combines aggressive social engineering (often using sexually explicit lures) with a devastating time-bomb payload designed to systematically overwrite and destroy critical user documents on the third day of every month.\n\n<h3>Infection Vector and Technical Capabilities</h3>\nNyxem propagates almost exclusively via email. It arrives with enticing subject lines (e.g., \"Miss Lebanon 2006,\" \"Kama Sutra pic,\" \"Fw: true romance\") and an attached executable, often disguised with a double extension (e.g., `.doc.exe` or `.pdf.zip`) or a provocative icon.\n\nUpon execution, Nyxem performs the following actions:\n<ul>\n<li><strong>Mass Mailing and Harvesting:</strong> The worm harvests email addresses from the local system (address books, cached web pages) and uses its own SMTP engine to aggressively mail copies of itself to all found contacts.</li>\n<li><strong>Security Software Neutralization:</strong> Nyxem actively hunts for and terminates processes related to antivirus software, firewalls, and security monitoring tools, effectively blinding the host.</li>\n<li><strong>The \"Time Bomb\" Payload (Destructive Data Wiping):</strong> The most critical feature of Nyxem is its destructive payload. It checks the system clock. On the 3rd day of every month, it activates a wiper routine that searches for and overwrites files with specific extensions (`.doc`, `.xls`, `.mdb`, `.mde`, `.ppt`, `.pps`, `.zip`, `.rar`, `.pdf`, `.psd`, `.dmp`) with the text \"DATA ERROR [47 0F 94 93 F4 K5].\"</li>\n</ul>\n\n<h3>Threat Assessment</h3>\nNyxem is classified as a critical, destructive threat. The \"time bomb\" payload ensures that if the infection is not caught within a specific window, the organization will suffer catastrophic, unrecoverable data loss across all infected endpoints. The mass-mailing capability also causes severe network congestion.\n\n<h3>Incident Response and Remediation</h3>\n<ul>\n<li><strong>Immediate Isolation and Clock Modification:</strong> If an active infection is suspected and it is nearing the 3rd of the month, immediately isolate the endpoint and, if necessary, alter the system clock to prevent the trigger condition from executing while remediation occurs.</li>\n<li><strong>Outbound SMTP Blocking:</strong> Block unauthorized outbound Port 25 (SMTP) traffic at the firewall to halt the worm's propagation.</li>\n<li><strong>Targeted Malware Removal:</strong> Run comprehensive anti-malware scans (often from a safe, bootable environment since the worm disables local AV). Because Nyxem *overwrites* files rather than encrypting them, recovery of the targeted documents requires restoring from offline, air-gapped backups.</li>\n</ul>",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [
    "W32.Nyxem",
    "Worm.KamaSutra",
    "W32/Blackmal",
    "Worm:Win32/MyWife"
  ],
  "enrichment_level": "insufficient_information",
  "faq": [],
  "faq_count": 0,
  "mitre_attack": [
    "T1566.001",
    "T1485",
    "T1562.001"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-07-02T07:10:57Z",
  "type": "Worm / Data Wiper",
  "target_industries": [
    "Global / Opportunistic"
  ],
  "motivation": "Opportunistic",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ]
}