Hostseditor

Overview

Executive Summary

Technical Exploitation and Capabilities

• Security Blocking: The malware adds entries that map the domains of major antivirus vendors (e.g., `update.symantec.com`, `microsoft.com`) to the local loopback address (`127.0.0.1`). This completely prevents the infected system from downloading critical antivirus definition updates or OS patches, leaving the system highly vulnerable.
• Phishing Redirection (Pharming): HostsEditor maps the domain names of popular banks, social media sites, or corporate portals to the IP address of a malicious server controlled by the attacker. When the user types the legitimate URL, they are silently redirected to a pixel-perfect fake login page designed to harvest their credentials.
• Adware Injection: Some variants redirect high-traffic domains to affiliate ad networks or servers hosting exploit kits.

Threat Impact

Incident Response and Remediation

• File Integrity Monitoring (FIM): The Windows `hosts` file rarely changes in modern enterprise environments. Deploy FIM solutions to immediately alert security teams to any unauthorized modifications to this file.
• Manual Remediation: The immediate fix requires administrative privileges. Open the `hosts` file in a text editor (like Notepad) and delete all unauthorized IP-to-domain mappings. A clean, default Windows `hosts` file should only contain commented lines (starting with `#`) and the localhost loopback entry.
• Root Cause Analysis: While fixing the file is trivial, responders must identify *what* modified it. Conduct a full antivirus scan and EDR review to locate the initial malware payload (the HostsEditor) that performed the modification.

Known aliases

Threat reports may refer to this family under multiple names:

• Trojan.Hosts
• Riskware.HostsEditor
• HackTool:Win32/HostsMod

MITRE ATT&CK Techniques

This family has been observed using the following ATT&CK techniques: T1562.004 T1112 T1562.001

Generated Detections (Boilerplate)

These YARA and Sigma rules are auto-generated based on the family name and aliases. They must be heavily tuned before deployment in a production environment.

YARA Rule

rule MALWARE_WIN_HOSTSEDITOR {
    meta:
        description = "Detects Hostseditor (trojan)"
        author = "SystemHelpdesk Boilerplate Generator"
        date = "2026-07-06"
    strings:
        $s1 = "hostseditor" ascii wide nocase
        $s2 = "trojan.hosts" ascii wide nocase
        $s3 = "riskware.hostseditor" ascii wide nocase
        $s4 = "hacktool:win32/hostsmod" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

Sigma Rule

title: Suspicious Hostseditor Activity
id: c5f726ddc3fe8084be346b3970dbae1a
status: experimental
description: Detects generic indicators of the hostseditor malware family.
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith:
            - '\cmd.exe'
            - '\powershell.exe'
        CommandLine|contains:
            - "*hostseditor*"
            - "*trojan.hosts*"
            - "*riskware.hostseditor*"
            - "*hacktool:win32/hostsmod*"
    condition: selection
level: medium

References & External Analysis

• Search "hostseditor" on VirusTotal (External Analysis)

Frequently Asked Questions

Related Families (Category: trojan)

Explore other malware families in the same category:

• Driverassist
• Sign0Fmisery
• Bifrose
• Ramnif
• Genericrxby

Machine-readable

Get this profile as JSON: https://jordanricky1604-ship-it.github.io/malware-families-catalog/api/hostseditor.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.