{
  "family": "nemesis",
  "sample_count": 103,
  "category": "trojan",
  "description": "Backdoor:Win32/Nemesis is a highly stealthy, targeted Remote Access Trojan (RAT) engineered to infiltrate corporate endpoints, establish a covert communication channel, and provide attackers with interactive control for espionage, data exfiltration, or the deployment of destructive payloads.<br><br><b>What is Nemesis?</b><br>For the victim, Nemesis provides zero visual indicators of compromise. For threat intelligence analysts, Nemesis represents a highly capable backdoor frequently utilized in targeted, advanced persistent threat (APT) attacks. It is designed to bypass initial security controls, harvest comprehensive system intelligence, and maintain long-term, undetected access to the victim network.<br><br><b>Infection Vectors & Threat Hunting</b><br>Nemesis is typically delivered via spearphishing campaigns containing weaponized Office documents (employing malicious VBA macros) or dropped as a secondary payload by exploit kits. Upon execution, it utilizes heavy packing and obfuscation to evade static antivirus signatures. It drops a randomized executable into the `%AppData%` or `%SystemRoot%` directories. Persistence is achieved by creating a hidden scheduled task or modifying the Registry Run keys. Nemesis frequently injects its core modules into legitimate system processes (like `svchost.exe`) to mask its outbound network traffic.<br><br><b>Forensic Analysis & Impact</b><br>Threat hunters should investigate EDR alerts for 'Suspicious Process Injection' or 'Anomalous Child Process Spawning'. Network logs will often reveal Nemesis reaching out to compromised domains using encrypted HTTP/HTTPS traffic. The presence of unexpected, hidden scheduled tasks designed to execute randomly named binaries in the user's profile is a strong IoC. Memory analysis is crucial to extract the injected modules and identify the specific C2 infrastructure.",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [],
  "enrichment_level": "expert-seo",
  "faq": [],
  "faq_count": 0,
  "mitre_attack": [
    "T1027",
    "T1055",
    "T1053.005",
    "T1105",
    "T1547.001"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-06-09",
  "mitre_attack_detail": [
    {
      "id": "T1055",
      "name": "Process Injection",
      "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"
    },
    {
      "id": "T1053.005",
      "name": "Scheduled Task/Job: Scheduled Task",
      "tactic": "Persistence"
    },
    {
      "id": "T1027",
      "name": "Obfuscated Files or Information",
      "tactic": "Defense Evasion"
    }
  ],
  "containment_steps": [
    "Instantly isolate the endpoint from the network to sever the attacker's interactive, remote-control session.",
    "Capture a full forensic memory image of the machine to extract the decrypted Nemesis payload and its C2 configuration.",
    "Audit the Windows Task Scheduler and Registry Run keys to identify and remove the Nemesis persistence mechanisms.",
    "Assume total endpoint compromise; perform a clean OS rebuild and force password resets for all accounts that accessed the machine."
  ],
  "what_to_avoid": [
    "Do not leave the machine connected to the network during triage; the attacker has live access and will likely destroy evidence or move laterally.",
    "Avoid relying solely on manual file deletion, as the injected processes will likely just recreate the dropped binaries."
  ],
  "target_industries": [
    "Global / Opportunistic"
  ],
  "motivation": "Opportunistic",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ]
}