Inbox

Overview

Inbox (widely cataloged across security solutions under designations including BrowserModifier:Win32/Inbox, Adware:Win32/Inbox, and PUA:Win32/InboxAce) is a pervasive browser hijacker and adware toolbar family developed by monetization networks (such as Mindspark/IAC). Distributed through deceptive software bundles, fake search bars, and free game installers, Inbox alters internet browser configurations across Google Chrome, Mozilla Firefox, and Internet Explorer. It silently modifies the default search engine, home page, and new tab settings to point to affiliate search engines (such as InboxAce search or customized Ask/MyWay portals). It injects commercial advertising banners, sponsored search results, and pop-up windows while monitoring browsing navigation and query keywords for behavioral advertising targeting.

Known aliases

Threat reports may refer to this family under multiple names:

• BrowserModifier:Win32/Inbox
• Adware:Win32/Inbox
• PUA:Win32/InboxAce
• Toolbar:Win32/Inbox
• Win32/InboxAce

MITRE ATT&CK Techniques

Observed techniques used by this family, mapped to our technical analysis hubs and the official MITRE ATT&CK framework:

Tactical Mitigations

Based on the techniques used by this family, consider the following defensive strategies:

• T1056.001: Implement Endpoint Detection and Response (EDR) to monitor for suspicious API calls related to keystroke interception. Enforce Multi-Factor Authentication (MFA) to render stolen passwords useless.
• T1071.001: Implement web filtering and SSL/TLS inspection to detect malicious command and control (C2) traffic hiding in HTTP/HTTPS.

MITRE D3FEND™ Defensive Countermeasures

Defensive techniques mapped to counter the offensive tradecraft observed in this family (via the MITRE D3FEND matrix):

Tiered Detection Rules (Cisco CAIRN Model)

Modern threat detection requires multi-layered rule engineering. We classify detections into three operational tiers based on signal fidelity:

rule MALWARE_WIN_INBOX_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Inbox"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "inbox" ascii wide nocase
        $s2 = "browsermodifier:win32/inbox" ascii wide nocase
        $s3 = "adware:win32/inbox" ascii wide nocase
        $s4 = "pua:win32/inboxace" ascii wide nocase
        $s5 = "toolbar:win32/inbox" ascii wide nocase
        $s6 = "win32/inboxace" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Inbox (Adware) Execution & Triage
id: bef49228-a600-51d5-9f31-c75c98ac61f0
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Inbox malware family. Detects suspicious execution from temporary user
  directories with hidden window flags and background transfer utilities.
references:
- https://malware-families-catalog.systemhelpdesk.com/families/inbox
- https://malware-families-catalog.systemhelpdesk.com/defensive/ransomware-protection
- https://malware-families-catalog.systemhelpdesk.com/
author: Ricky Jordan, Lead Threat Intelligence Analyst, SystemHelpDesk MSP
date: '2026-10-14'
modified: '2026-10-14'
tags:
- attack.adware
- author.ricky-jordan
- source.systemhelpdesk-mfc
- attack.t1189
- attack.t1112
- attack.t1547_001
- attack.t1056_001
- attack.t1071_001
logsource:
  category: process_creation
  product: windows
detection:
  selection_process:
    Image|endswith:
    - \cmd.exe
    - \powershell.exe
    - \cscript.exe
    - \wscript.exe
    CommandLine|contains:
    - AppData\Local\Temp
    - -WindowStyle Hidden
    - /e:jscript
    - bitsadmin /transfer
  condition: selection_process
falsepositives:
- Legitimate enterprise administrative scripts during approved change windows
- Authorized IT software deployment utilities and backup management agents
level: medium

rule MALWARE_WIN_INBOX_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Inbox tradecraft"
        tier = "T3 - Attribution Fingerprint"
        confidence = "High (Confirmed Family Signature)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        // Core family identifier & heuristic payload signatures
        $attrib_str = "inbox" ascii wide nocase
        $pe_magic = "MZ" ascii
        $net_marker = "http" ascii nocase
    condition:
        uint16(0) == 0x5a4d and ($attrib_str and $net_marker) and filesize < 15MB
}

Containment & Response Steps

Ordered checklist for responders. Adapt to your environment and engage professional support for active incidents.

1. Terminate active browser processes and associated toolbar helper applications.
2. Uninstall the Inbox toolbar via Windows Programs and Features.
3. Remove rogue Inbox extensions and add-ons across Chrome, Firefox, and Edge.
4. Restore browser default search provider, start page, and new tab URLs.
5. Run a full antimalware scan to purge persistent registry modifications and cache files.

What to Avoid

Common mistakes during response to this family that can destroy evidence, spread the infection, or worsen recovery.

1. Do not click on sponsored search links or promotional banners injected by the toolbar.
2. Do not agree to bundle offers during third-party freeware installations.

References & External Analysis

• Microsoft Defender Threat Encyclopedia - BrowserModifier:Win32/Inbox
• Malwarebytes Labs - Adware.Inbox Toolbar Removal Guide
• Sophos Threat Center - Inbox Toolbar Detection
• Search "inbox" on VirusTotal (External Analysis)
• Search "inbox" on Any.Run (Sandbox Sandbox)
• Search "inbox" on MalwareBazaar (Malware Samples)

Frequently Asked Questions

Related Threats (Category: Adware)

Explore other documented threats in the same operational category:

• Temonde
• Youxun
• Opensupdater
• Boilod
• Installerex
• Shyape
• Gjue
• Techsnab

Machine-readable

Get this profile as JSON: https://malware-families-catalog.systemhelpdesk.com/api/inbox.json

Ecosystem & Interactive Environments

This profile is part of the Malware Families Catalog, a public dataset of 2,899 malware families. The catalog is also published across our ecosystem: Hugging Face, Kaggle, Zenodo, Replit, StackBlitz, CodeSandbox, and CodePen.