Gamarue

Category: loader · Aliases: Andromeda, Wauchos, Gamarue · Sample count (EMBER 2018): 2,789 · Enrichment: curated_sourced · Updated: 2026-10-14
Category: LoaderSeverity: CRITICALStatus: Automated SignaturePlatform: WINDOWS_PEStage: Initial Access, Execution, LoaderFirst seen: 2011Actor: Unknown / CybercriminalIndustry: Global / OpportunisticMotivation: Opportunistic🕸 Explore Relationship Graph⚙ API JSON⚡ Sigma Rule💾 YARA RuleOS: Windows 11, Windows 10, Windows Server 2022
Executive Summary
Gamarue (widely tracked by security vendors as Andromeda or Wauchos) is one of the most prolific and technically sophisticated modular botnet loaders in the history of cybercrime.

Table of Contents

Overview

Gamarue (widely tracked by security vendors as Andromeda or Wauchos) is one of the most prolific and technically sophisticated modular botnet loaders in the history of cybercrime. First marketed on Russian-language underground forums in September 2011 for roughly $1,500, Gamarue functioned as a premier distribution backbone for international cybercrime syndicates, responsible for deploying banking trojans (such as Ursnif and Citadel), spambots, click-fraud kits, and ransomware across millions of consumer and enterprise endpoints. The malware is engineered in C with an extraordinarily compact core payload (< 30 KB) designed to evade behavioral sandboxes through rigorous anti-analysis routines. Gamarue checks for VMware, VirtualBox, and QEMU artifacts, verifies volume serial numbers, detects user-mode API hooking, and uses custom API hashing to resolve system functions dynamically. Upon establishing persistence, the modular architecture allowed operators to deploy specialized plugins: a formgrabber for browser credential theft, a rootkit for kernel-level concealment, a Socks4/5 proxy module for traffic relaying, and a TeamViewer reverse proxy module for unauthorized remote desktop control. In December 2017, an unprecedented multinational law enforcement operation led by the FBI, Europol's European Cybercrime Centre (EC3), the Joint Cybercrime Action Taskforce (J-CAT), the Luneburg Police in Germany, and Microsoft dismantled the global Andromeda infrastructure. The operation sinkholed approximately 1,500 command-and-control domains, intercepted telemetry from over 1.1 million infected computers per month across 223 countries, and led to the arrest of a key syndicate operative in Belarus.

Known aliases

Threat reports may refer to this family under multiple names:

Threat Actor Attribution

Attribution is probabilistic, not a science. Each link below states its confidence level and the evidence behind it.

→ Explore all Threat Actor & APT Campaign Profiles

Family Pedigree & Lineage

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

Known Derivatives & Downstream Variants: Andromeda V2.06 · Andromeda V2.09 · Wauchos V1.5

MITRE ATT&CK Techniques

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

→ Explore the complete 226-Technique ATT&CK Threat Matrix

Tactical Mitigations

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

MITRE D3FEND™ Defensive Countermeasures

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

D3FEND IDCountermeasure NameTacticCountered ATT&CKDefensive Guidance
D3-BDABinary De-obfuscation & UnpackingAnalyzeT1027Utilize memory dump scanners and entropy inspection to unpack encrypted stagers during process creation.
D3-PHAProcess Hollowing AnalysisDetectT1055.012Inspect unbacked executable memory regions (PAGE_EXECUTE_READWRITE) for replaced PE image headers inside legitimate host processes.
D3-WAFWeb Content Filtering & InspectionFilterT1071.001Block newly registered domains (NRDs) and inspect HTTP Host and URI headers for known C2 profiles.
D3-NTINetwork Traffic InspectionDetectT1105Inspect deep packet payloads for anomalous staging binaries and unauthorized egress protocols.
D3-EEDExecution Environment DetectionDetectT1497.001Configure malware sandboxes to emulate legitimate hardware metrics, realistic mouse movements, and valid system uptimes.
D3-RPMRegistry Persistence MonitoringDetectT1547.001Audit and restrict write privileges to user and machine-level Registry Run/RunOnce keys using Endpoint Privilege Management.

Exploited Vulnerabilities (CVEs)

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

Command & Control (C2) and Network Profile

How this family talks to its operators. C2 traffic can often identify a family even when its code and configuration are hard to analyse. Ports and patterns are historical and change between campaigns, so use them as hunting leads rather than block-only rules.

ProtocolsHTTP, TCP
Observed ports80, 443, 8080
Infrastructure modelHundreds of fast-flux and geographically distributed Apache/PHP control panels resolving through dynamic DNS and hijacked top-level domains.
Encryption / encodingHTTP POST requests containing encrypted payloads wrapped in custom RC4 encryption with hardcoded keys, followed by Base64 encoding and JSON-like structural formatting.
Traffic fingerprintRepetitive HTTP POST requests with faux image file extensions (e.g. /image.png, /logo.gif) transmitting fixed-length encrypted binary headers containing infected computer volume serials and bot IDs.
Identifiable from traffic aloneHigh

Network detection ideas

Sources: Europol Press Release: Andromeda Botnet Dismantled, CISA / US-CERT Alert TA17-339A: Andromeda / Gamarue Malware

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.

Delivery vectors

Persistence mechanisms

SIEM / EDR Ingestion: Need these reference indicators for threat hunting?

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:

Tier 1 Primitive Artifact Rule (Fast Triage)

Matches raw strings and file markers. Vulnerable to binary repacking and simple obfuscation.

rule MALWARE_WIN_GAMARUE_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Gamarue"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "gamarue" ascii wide nocase
        $s2 = "andromeda" ascii wide nocase
        $s3 = "wauchos" ascii wide nocase
        $s4 = "gamarue" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

Tier 2 Behavioral Context Rule (Process Chains & Sigma)

Tracks parent-child process anomalies and suspicious scripting telemetry. Resilient against file renames.

title: SystemHelpDesk Detection - Gamarue (Loader) Execution & Triage
id: ab5a5883-1f86-550e-aa53-fa5b8e5af0ed
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Gamarue 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/gamarue
- 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.loader
- author.ricky-jordan
- source.systemhelpdesk-mfc
- attack.t1055_012
- attack.t1140
- attack.t1497_001
- attack.t1105
- 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

Tier 3 Attribution Fingerprint Rule (High Fidelity)

Deep signature matching distinctive operational fingerprints and payload characteristics.

rule MALWARE_WIN_GAMARUE_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Gamarue 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 = "gamarue" 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
}
SOC & SIEM Rule Downloads: ⬇ Download YARA Rule (.yar) ⬇ Download Sigma Rule (YAML) ⬇ Download Sigma Rule (JSON) ⚙ Threat Profile API (JSON)

Containment & Response Steps

Home Users: If you suspect a malware infection on your personal device, disconnect from the internet immediately and run a full system scan with your antivirus software (see our TotalAV Antivirus & Security Support Guide). The steps below are intended for IT professionals responding to enterprise incidents.

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

  1. Sever network connection to stop Gamarue from pulling down destructive secondary payloads.
  2. Perform memory forensics to identify process injection inside explorer.exe, svchost.exe, or msiexec.exe.
  3. Remove rogue registry startup entries and scheduled tasks created by the loader.
  4. Inspect perimeter proxy logs for repeated HTTP POST beacons with faux image extensions.
  5. Submit memory dumps to endpoint detection systems to verify no dormant rootkit modules remain active.

What to Avoid

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

  1. Do not assume the infection is benign just because no ransomware is active; Gamarue is primarily a delivery system for secondary banking trojans and wipers.
  2. Do not restart endpoints prior to capturing volatile memory if live forensic attribution is required.

References & External Analysis

North American Authority Advisory (CISA / NIST)

The Cybersecurity and Infrastructure Security Agency (CISA) has published an official US federal advisory on this family, which can be mapped to NIST Cybersecurity Framework (CSF) incident response controls: US-CERT Alert TA17-339A (Andromeda / Gamarue Malware Disruption) ↗

Frequently Asked Questions

What is Gamarue / Andromeda?

Gamarue (also known as Andromeda or Wauchos) is a prominent modular botnet loader created in 2011 that infected over a million computers monthly, serving as a gateway to install ransomware and banking trojans.

When was the Andromeda botnet dismantled?

Andromeda was taken down in December 2017 through a multinational effort by the FBI, Europol EC3, German Luneburg Police, and Microsoft, resulting in the sinkholing of 1,500 C2 domains and the arrest of a key operative.

What secondary malware did Gamarue deploy?

Gamarue was hired by numerous cybercriminal syndicates to drop payloads such as the Ursnif banking trojan, Citadel, spambots, and ransomware.

How did Gamarue evade analysis?

Gamarue performed deep sandbox checks for virtual machine environments (VMware, VirtualBox, QEMU), validated hardware serial numbers, and unhooked system APIs before injecting into legitimate Windows processes.

How can incident responders detect Gamarue on the network?

By monitoring for HTTP POST beacons to unusual external IPs disguised as image files (.png/.gif) containing RC4-encrypted system volume serials.

How do I remove Gamarue from Windows?

Manual removal of Gamarue is highly discouraged as it may leave persistence mechanisms intact. We recommend disconnecting the device from the internet and utilizing a professional incident response service or enterprise-grade EDR software to conduct a full forensic sweep.

What are the main symptoms of a Gamarue infection?

Symptoms of Gamarue can include unexpected system slowness, unauthorized outbound network traffic to unknown IP addresses, disabled security software, and suspicious background processes running from AppData or Temp directories.

Protect Your Network Against Loaders

Want to prevent Gamarue and similar threats from compromising your organization? Read our comprehensive defensive guide: Think You've Been Hacked? What To Do First.

📣 Threat Intel Correction or Update?

Notice an outdated IOC, unlisted alias, or disputed attribution? Threat researchers are invited to propose an update on GitHub or contact the SystemHelpDesk research desk. All community revisions are credited in our public CHANGELOG.

Need help with an active incident? Published by the SystemHelpdesk team.

Machine-readable

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