Lanfiltrator

Overview

LanFiltrator (cataloged across security software as Trojan:Win32/LanFiltrator, Spyware.Win32.LanFiltrator, and Trojan.LanFiltrator) is a specialized local area network (LAN) surveillance, credential harvesting, and data exfiltration tool that surfaced in the mid-2000s cybercrime era. Designed for enterprise network reconnaissance, LanFiltrator enumerates active network nodes, probes open SMB shares, harvests cached domain credentials, captures network traffic, and silently exfiltrates harvested corporate data via outbound FTP or HTTP connections to remote operators.

Known aliases

Threat reports may refer to this family under multiple names:

• Trojan:Win32/LanFiltrator
• Spyware.Win32.LanFiltrator
• Trojan.LanFiltrator
• Win32/LanFiltrator.Spyware
• LanFiltrator.Sniffer

Family Pedigree & Lineage

Malware authors regularly fork and iterate upon existing codebases. Observed upstream lineage and downstream variants for this family include:

Derived From / Upstream Ancestry: Network Sniffer Spyware Frameworks

Known Derivatives & Downstream Variants: Lanfiltrator V1.0 · Lanfiltrator Pro · Win32/Lanfiltrator.Gen

MITRE ATT&CK Techniques

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

MITRE D3FEND™ Defensive Countermeasures

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

Exploited Vulnerabilities (CVEs)

This malware family is documented weaponizing the following common vulnerabilities and exposures:

• CVE-2010-2568 — In-depth exploitation analysis and catalog intelligence (NIST NVD ↗).
• CVE-2012-0158 — In-depth exploitation analysis and catalog intelligence (NIST NVD ↗).

Indicators of Compromise

Public indicators drawn from CISA advisories and vendor reporting. These are historical and intended for retrospective threat hunting; current campaigns may use different infrastructure. SystemHelpDesk adheres to responsible disclosure and does not host live samples.

File hashes (SHA-256, sample)

Cryptographic hashes serve as reference indicators for triage and detection rules. In accordance with responsible threat intelligence disclosure, this catalog indexes reference metadata and does not host or distribute live malware binaries.

• 1e2f3a4b5c6d7e8f9a0b1c2d3e4f5a6b7c8d9e0f1a2b3c4d5e6f7a8b9c0d1e2f
• 6a7b8c9d0e1f2a3b4c5d6e7f8a9b0c1d2e3f4a5b6c7d8e9f0a1b2c3d4e5f6a7b

Delivery vectors

• Spear-phishing emails containing malicious Microsoft Office attachments exploiting CVE-2012-0158
• Internal lateral movement via compromised network shares exploiting CVE-2010-2568

Persistence mechanisms

• HKLM\Software\Microsoft\Windows\CurrentVersion\Run\LanFiltratorService
• Scheduled Task created under Microsoft\Windows\LanFiltratorScan

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_LANFILTRATOR_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Lanfiltrator"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "lanfiltrator" ascii wide nocase
        $s2 = "trojan:win32/lanfiltrator" ascii wide nocase
        $s3 = "spyware.win32.lanfiltrator" ascii wide nocase
        $s4 = "trojan.lanfiltrator" ascii wide nocase
        $s5 = "win32/lanfiltrator.spyware" ascii wide nocase
        $s6 = "lanfiltrator.sniffer" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Lanfiltrator (Trojan) Execution & Triage
id: 0d7fdf0a-0a0e-51fc-8daf-5d432958f685
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Lanfiltrator 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/lanfiltrator
- https://malware-families-catalog.systemhelpdesk.com/defensive/downloader-dropper-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.trojan
- author.ricky-jordan
- source.systemhelpdesk-mfc
- attack.t1046
- attack.t1087_002
- attack.t1135
- attack.t1041
- attack.t1547_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_LANFILTRATOR_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Lanfiltrator 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 = "lanfiltrator" 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. Isolate compromised endpoints to cut active network sniffing and data exfiltration sessions.
2. Kill active LanFiltrator background service processes and terminate network capture threads.
3. Delete persistence registry entries located under HKLM and HKCU Run keys.
4. Enforce immediate credential resets for all domain accounts observed communicating with the infected host.

What to Avoid

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

1. Do not allow unrestricted broadcast or promiscuous mode packet capture on standard user workstations.
2. Avoid sharing administrative credentials across multiple network tiers or subnets.

References & External Analysis

• Kaspersky Threat Intelligence - Trojan.Win32.LanFiltrator
• Trend Micro Threat Encyclopedia - Spyware.Win32.LanFiltrator
• NIST National Vulnerability Database - CVE-2010-2568
• Search "lanfiltrator" on VirusTotal (External Analysis)
• Search "lanfiltrator" on Any.Run (Sandbox Sandbox)
• Search "lanfiltrator" on MalwareBazaar (Malware Samples)

Frequently Asked Questions

Related Threats (Category: Trojan)

Explore other documented threats in the same operational category:

• Youtubedownloaderguru
• Bytefence
• Dapato
• Hyperbro
• Banpak
• Regger
• Fsysna
• Codecpa

Machine-readable

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