{
  "family": "inno",
  "sample_count": 5,
  "category": "advanced_threat",
  "description": "Adware:Win32/Inno (often detected due to the malicious abuse of the legitimate **Inno Setup** compiler) is a pervasive commercial software bundling framework and adware injection platform. It is designed to take legitimate freeware and 'wrap' it in a deceptive installer created with Inno Setup that uses 'Dark Patterns' to trick users into installing multiple aggressive adware payloads and browser hijackers alongside the desired software.<br><br><b>Understanding Malicious Inno Setup Wrappers</b><br>To an end-user, the infection appears as a standard software setup wizard. For an enterprise, it represents a significant risk of 'alert fatigue' for the SOC. The developers of the wrapper operate on a Pay-Per-Install (PPI) model, receiving financial compensation from adware vendors for every successful installation. They specifically abuse the widely trusted Inno Setup compiler to evade generic AV detection.<br><br><b>Execution and Deceptive Installation Mechanics</b><br>Inno is almost exclusively encountered when users download software from untrustworthy, third-party software aggregators rather than official vendor sites (`T1204.002`). Upon execution, the Inno-compiled wrapper initiates (`T1189`). It employs Dark Patterns, such as pre-checked 'Accept' boxes buried deep in the EULA, or confusingly worded 'Decline' buttons that actually accept the offer (`T1036`). The secondary payloads then establish persistence (often via Scheduled Tasks or Registry Run keys) (`T1547.001`) and begin injecting ads into web browsers or hijacking the default search engine (`T1562.001`). Advanced variants use embedded Pascal scripting within the Inno installer to dynamically pull down payloads based on the victim's geolocation.<br><br><b>Indicators of Compromise & Impact</b><br>The primary impact is a severely degraded user experience and unauthorized tracking. IoCs include EDR alerts for a single downloaded executable (e.g., `setup.exe`) dropping and executing multiple unrelated adware binaries from the `%Temp%` directory. The user will often report a suddenly changed browser homepage, new toolbars, or excessive pop-up advertisements.",
  "cta": "Published by the SystemHelpdesk team.",
  "aliases": [],
  "enrichment_level": "expert-seo",
  "faq": [],
  "faq_count": 0,
  "mitre_attack": [
    "T1562.001",
    "T1036",
    "T1204.002",
    "T1189"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-06-09",
  "mitre_attack_detail": [
    {
      "id": "T1189",
      "name": "Drive-by Compromise (Deceptive software bundling)",
      "tactic": "Initial Access"
    },
    {
      "id": "T1204.002",
      "name": "User Execution: Malicious File (User running the wrapper)",
      "tactic": "Execution"
    },
    {
      "id": "T1036",
      "name": "Masquerading (Disguising adware consent forms)",
      "tactic": "Defense Evasion"
    },
    {
      "id": "T1562.001",
      "name": "Impair Defenses: Disable or Modify Tools (Browser hijacking)",
      "tactic": "Defense Evasion"
    }
  ],
  "containment_steps": [
    "Use the Windows Control Panel to thoroughly uninstall the explicitly named adware programs that were dropped by the Inno wrapper.",
    "Run an enterprise-grade Adware/PUA removal tool (such as Malwarebytes) to strip the deep registry hooks and browser extensions left behind.",
    "Reset all installed web browsers (Chrome, Edge, Firefox) to their factory default settings to remove any lingering homepage or search engine hijackers.",
    "Review the user's internet history to identify the deceptive download portal that distributed the package, and block it via the corporate proxy."
  ],
  "what_to_avoid": [
    "Do not allow users local administrator privileges; standard users cannot typically install the system-level services required by aggressive adware bundles.",
    "Avoid relying solely on manual uninstallation, as PPI wrappers often drop 'watchdog' processes designed to reinstall the adware if it is removed."
  ],
  "target_industries": [
    "Global / Opportunistic"
  ],
  "motivation": "Opportunistic",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ]
}