{
  "family": "woozlist",
  "sample_count": 14,
  "category": "browser_modifier",
  "description": "WoozList (classified as BrowserModifier:Win32/WoozList and Adware:Win32/WoozList across Microsoft Defender, Malwarebytes, and Trend Micro) is a persistent adware toolbar and browser hijacker. Bundled with freeware utilities and media converters, WoozList forces unwanted modifications across Chrome, Firefox, and Edge browsers. It changes default search engines, replaces start pages with ad-monetized portal domains, and injects sponsored search results and pop-under commercial banners into web sessions. WoozList creates autostart registry entries and persistent background updater services to resist manual uninstallation.",
  "cta": "Published by the SystemHelpdesk Threat Intelligence Team.",
  "aliases": [
    "BrowserModifier:Win32/WoozList",
    "Adware:Win32/WoozList",
    "PUA:Win32/WoozList",
    "WoozList Toolbar",
    "Win32/WoozList"
  ],
  "enrichment_level": "curated_sourced",
  "faq": [
    {
      "@type": "Question",
      "name": "What is BrowserModifier:Win32/WoozList?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "WoozList is an adware program and browser modifier that alters search engines and injects commercial ads into browsers."
      }
    },
    {
      "@type": "Question",
      "name": "How does WoozList get installed?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "It is bundled into freeware downloaders, media converters, and deceptive online software installation wizards."
      }
    },
    {
      "@type": "Question",
      "name": "What browser changes are made by WoozList?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "It modifies default search providers, alters browser homepages, and installs ad-injecting browser extensions."
      }
    },
    {
      "@type": "Question",
      "name": "How does WoozList persist on Windows systems?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "It registers background updater services and adds autostart values to Windows Run registry keys."
      }
    },
    {
      "@type": "Question",
      "name": "How do you completely remove WoozList?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Uninstall WoozList via Windows Settings, remove rogue browser extensions, and reset browser search preferences."
      }
    }
  ],
  "faq_count": 5,
  "mitre_attack": [
    "T1176",
    "T1547.001",
    "T1053.005",
    "T1112",
    "T1071.001"
  ],
  "cisa_advisory": null,
  "last_updated": "2026-10-15",
  "mitre_attack_detail": [
    {
      "id": "T1189",
      "name": "Drive-by Compromise",
      "tactic": "Initial Access"
    },
    {
      "id": "T1176",
      "name": "Browser Extensions",
      "tactic": "Persistence"
    },
    {
      "id": "T1112",
      "name": "Modify Registry",
      "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"
    }
  ],
  "containment_steps": [
    "Quarantine the endpoint to halt the active exfiltration of browsing telemetry and the downloading of further adware modules.",
    "Audit Windows Group Policies and the Registry to remove any forced extension installation policies created by the adware.",
    "Deploy an enterprise adware removal tool (e.g., AdwCleaner) to locate and strip the deeply embedded registry hooks and watchdog services.",
    "Force a complete reset of all installed web browsers to factory defaults to eradicate the rogue extensions and restore the homepage."
  ],
  "what_to_avoid": [
    "Do not rely solely on the browser's 'remove extension' button; Woozlist frequently uses GPOs and watchdog services to immediately reinstall itself.",
    "Avoid ignoring the infection; adware tracking data is highly detailed and may expose corporate activities or access to internal portals."
  ],
  "target_industries": [
    "Global / Opportunistic"
  ],
  "motivation": "Opportunistic",
  "threat_actors": [
    "Unknown / Cybercriminal"
  ],
  "target_geographies": [
    "Global"
  ],
  "attack_stage": [
    "execution",
    "persistence"
  ],
  "ecosystem": [
    "windows_pe"
  ],
  "is_emerging": false,
  "sources": [
    {
      "name": "Microsoft Defender Threat Encyclopedia - BrowserModifier:Win32/WoozList",
      "url": "https://www.microsoft.com/en-us/wdsi/threats/malware-encyclopedia-description?Name=BrowserModifier:Win32/WoozList"
    },
    {
      "name": "Trend Micro Security Research - BrowserModifier.Win32.WoozList",
      "url": "https://www.trendmicro.com/vinfo/us/threat-encyclopedia/malware/browsermodifier.win32.woozlist"
    },
    {
      "name": "MITRE ATT&CK - Browser Extensions (T1176)",
      "url": "https://attack.mitre.org/techniques/T1176/"
    }
  ],
  "target_platforms": [
    "Windows 11",
    "Windows 10",
    "Windows 7"
  ]
}