{
  "family": "ekstak",
  "sample_count": 421,
  "category": "trojan_generic",
  "description": "Trojan:Win32/Ekstak is a stealthy trojan designed to silently infiltrate systems, establish a persistent backdoor, and act as a reliable downloader for secondary, highly destructive payloads.<br><br><b>Understanding Ekstak</b><br>To an end-user, an Ekstak infection is entirely transparent. For threat intelligence analysts, Ekstak is a critical indicator of a broader compromise. It functions as an 'Initial Access Broker' tool. Its sole purpose is to securely bypass endpoint defenses, profile the infected machine, and reach out to a Command-and-Control (C2) server to pull down the final payload, which is frequently ransomware or an advanced banking trojan.<br><br><b>Execution and Evasion Strategies</b><br>Ekstak is commonly distributed via weaponized email attachments (spearphishing) or malicious links. Upon execution, it utilizes heavy packing and obfuscation to evade static antivirus signatures. It drops a randomized executable into the <code>%Temp%</code> or <code>%LocalAppData%</code> directories. Persistence is achieved by creating a hidden scheduled task that executes the payload at system startup or user logon. Ekstak often injects its downloading routine into legitimate processes (like <code>explorer.exe</code>) to hide its outbound network traffic.<br><br><b>Indicators of Compromise (IoCs)</b><br>Threat hunters should investigate EDR alerts related to 'Suspicious Process Injection' or 'Anomalous Child Process Spawning'. Network logs will often reveal Ekstak reaching out to compromised domains using encrypted HTTPS traffic. The presence of unexpected, hidden scheduled tasks designed to execute randomly named, highly entropic binaries in the user's profile is a strong IoC. Memory analysis is necessary to extract the injected modules.",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [],
  "enrichment_level": "expert-seo",
  "faq": [],
  "faq_count": 0,
  "mitre_attack": [
    "T1105",
    "T1566.001",
    "T1027",
    "T1053.005",
    "T1055"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-06-09",
  "mitre_attack_detail": [
    {
      "id": "T1105",
      "name": "Ingress Tool Transfer",
      "tactic": "Command and Control"
    },
    {
      "id": "T1055",
      "name": "Process Injection",
      "tactic": "Defense Evasion"
    },
    {
      "id": "T1053.005",
      "name": "Scheduled Task/Job: Scheduled Task",
      "tactic": "Persistence"
    },
    {
      "id": "T1566.001",
      "name": "Phishing: Spearphishing Attachment",
      "tactic": "Initial Access"
    },
    {
      "id": "T1027",
      "name": "Obfuscated Files or Information",
      "tactic": "Defense Evasion"
    }
  ],
  "containment_steps": [
    "Isolate the endpoint immediately to prevent Ekstak from downloading and executing its secondary payloads (e.g., ransomware).",
    "Audit the Windows Task Scheduler and Registry Run keys to identify and remove the Ekstak persistence mechanisms.",
    "Review firewall and proxy logs to identify the C2 domains Ekstak attempted to contact, and block them enterprise-wide.",
    "Capture a live memory image (RAM dump) to extract the injected Ekstak modules and identify the secondary payloads."
  ],
  "what_to_avoid": [
    "Do not close an incident simply because the initial Ekstak dropper was quarantined; always verify if secondary payloads were downloaded.",
    "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"
  ]
}