{
  "family": "neksminer",
  "sample_count": 25,
  "category": "ransomware",
  "description": "Trojan:Win32/Neksminer is a specialized, stealthy cryptocurrency mining trojan designed to hijack the CPU and GPU resources of infected endpoints to illicitly mine digital currencies (typically Monero) for the threat actor.<br><br><b>Understanding Neksminer</b><br>To the victim, a Neksminer infection manifests as severe system sluggishness, high fan speeds, and unresponsive applications. For a security analyst, Neksminer represents a 'Cryptojacking' threat. Unlike ransomware, which announces its presence, Neksminer's goal is long-term stealth. It aims to remain undetected on corporate networks, quietly siphoning computational power and electricity, which can lead to significant hardware degradation and increased cloud computing costs.<br><br><b>Execution and Cryptojacking Evasion</b><br>Neksminer is typically distributed via drive-by downloads, exploit kits, or bundled with pirated software (`T1189`). Upon execution, it drops a modified, open-source mining executable (such as XMRig) into a hidden folder in `%AppData%`. To evade detection, it employs Process Hollowing (`T1055.012`), injecting the mining code into a legitimate Windows process like `svchost.exe`, `notepad.exe`, or `conhost.exe`. Advanced variants include a watchdog mechanism: if the user opens Task Manager (`taskmgr.exe`), the malware instantly suspends the mining operation to hide the CPU spike, resuming only when Task Manager is closed (`T1562.001`).<br><br><b>Indicators of Compromise & Impact</b><br>The primary impact is resource exhaustion (`T1496`) and financial loss (electricity/cloud billing). EDR platforms should alert on process hollowing into system executables. Network logs will reveal the malware communicating with known cryptocurrency mining pools (e.g., via the Stratum protocol) over non-standard ports (like TCP 3333 or 14444). Anomalous, sustained CPU usage near 100% across multiple endpoints is a strong indicator of a cryptojacking botnet.",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [],
  "enrichment_level": "expert-seo",
  "faq": [],
  "faq_count": 0,
  "mitre_attack": [
    "T1496",
    "T1105",
    "T1055.012",
    "T1547.001",
    "T1562.001"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-06-09",
  "mitre_attack_detail": [
    {
      "id": "T1496",
      "name": "Resource Hijacking",
      "tactic": "Impact"
    },
    {
      "id": "T1055.012",
      "name": "Process Injection: Process Hollowing",
      "tactic": "Defense Evasion"
    },
    {
      "id": "T1562.001",
      "name": "Impair Defenses: Disable or Modify Tools",
      "tactic": "Defense Evasion"
    },
    {
      "id": "T1105",
      "name": "Ingress Tool Transfer",
      "tactic": "Command and Control"
    },
    {
      "id": "T1547.001",
      "name": "Boot or Logon Autostart Execution: Registry Run Keys / Startup Folder",
      "tactic": "Persistence"
    }
  ],
  "containment_steps": [
    "Isolate the endpoint from the network to sever the malware's connection to its mining pool, halting its ability to receive new hashing tasks.",
    "Use EDR tools to identify the hollowed system process (e.g., svchost.exe consuming massive CPU) and terminate the specific malicious PID.",
    "Audit firewall logs for Stratum protocol traffic or connections to known mining pool IP addresses and block them enterprise-wide.",
    "Check for and remove persistent scheduled tasks or registry keys ensuring the miner restarts upon reboot."
  ],
  "what_to_avoid": [
    "Do not rely solely on Task Manager to diagnose the issue; sophisticated miners pause execution when monitoring tools are opened.",
    "Avoid treating cryptojacking as a low-priority 'nuisance' threat; if the attacker could deploy a miner, they could have deployed ransomware."
  ],
  "target_industries": [
    "Global / Opportunistic"
  ],
  "motivation": "Opportunistic",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ]
}