{
  "family": "installbrain",
  "sample_count": 13,
  "category": "advanced_threat",
  "description": "Adware:Win32/Installbrain is a widespread Potentially Unwanted Program (PUA) and adware bundler framework. It is designed to act as an aggressive installer wrapper that delivers a payload of legitimate freeware alongside multiple, hidden adware applications, browser hijackers, and tracking cookies.<br><br><b>Understanding Installbrain</b><br>To an end-user, Installbrain simply looks like the setup wizard for a free program they intentionally downloaded (like a PDF converter or a game). However, the wizard is heavily laden with 'Dark Patterns'—pre-checked consent boxes hidden under 'Advanced' settings. For security analysts, Installbrain is a primary delivery mechanism for the Pay-Per-Install (PPI) adware ecosystem. The creator of the wrapper gets paid by various adware vendors for every machine they successfully infect.<br><br><b>Execution and Bundling Mechanics</b><br>The user initiates the infection by running the downloaded installer (`T1204.002`). Installbrain immediately reaches out to a remote C2 server to fetch the latest list of 'offers' (adware payloads) tailored to the user's geolocation (`T1105`). If the user rapidly clicks 'Next' through the installation, it silently drops and executes multiple secondary MSIs or EXEs (`T1059.004`). These secondary payloads typically install rogue browser extensions (`T1176`), modify the browser's default search engine (`T1112`), and establish persistence via Scheduled Tasks to ensure the adware is reinstalled if removed.<br><br><b>Indicators of Compromise & Impact</b><br>The immediate impact is a severely degraded browsing experience, characterized by pop-up ads, redirected searches, and sluggish system performance. Incident responders will observe a sudden spike in DNS requests to known adware domains immediately following the execution of a newly downloaded installer. EDR logs will flag the original installer process spawning multiple child processes (the adware droppers) that subsequently modify browser preference files and Registry run keys.",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [],
  "enrichment_level": "expert-seo",
  "faq": [],
  "faq_count": 0,
  "mitre_attack": [
    "T1105",
    "T1112",
    "T1059.004",
    "T1204.002",
    "T1176"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-06-09",
  "mitre_attack_detail": [
    {
      "id": "T1204.002",
      "name": "User Execution: Malicious File",
      "tactic": "Execution"
    },
    {
      "id": "T1105",
      "name": "Ingress Tool Transfer",
      "tactic": "Command and Control"
    },
    {
      "id": "T1176",
      "name": "Browser Extensions",
      "tactic": "Persistence"
    },
    {
      "id": "T1059.004",
      "name": "Command and Scripting Interpreter: Unix Shell (or Windows CMD/Batch)",
      "tactic": "Execution"
    },
    {
      "id": "T1112",
      "name": "Modify Registry",
      "tactic": "Defense Evasion"
    }
  ],
  "containment_steps": [
    "Use the Windows Control Panel to systematically identify and uninstall all recently added programs, focusing on toolbars and 'search protectors'.",
    "Deploy an enterprise adware removal tool (e.g., AdwCleaner) to strip the deeply embedded Scheduled Tasks and registry hooks left behind by the adware framework.",
    "Force a complete reset of all installed web browsers (Chrome, Edge, Firefox) to factory defaults to eradicate rogue extensions and restore the homepage.",
    "Quarantine the original installer file to prevent further execution."
  ],
  "what_to_avoid": [
    "Do not rely solely on manual uninstallation via the Control Panel; the payloads frequently use watchdog services to immediately reinstall themselves.",
    "Avoid ignoring the infection; adware tracking data is highly detailed and may expose corporate activities or provide a foothold for more severe malvertising attacks."
  ],
  "target_industries": [
    "Global / Opportunistic"
  ],
  "motivation": "Opportunistic",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ]
}