Minerbot

Overview

Trojan:Win32/Minerbot (often a generic detection for **Cryptojacking Botnets**) represents a massive class of malware whose sole purpose is to silently hijack the computing resources (CPU and GPU) of infected endpoints to mine cryptocurrency (most commonly Monero/XMR) for the attacker. While it does not typically steal data, Minerbot infections cause severe physical strain on hardware and massive electricity costs for enterprises.

Understanding Minerbot Cryptojackers
To an end-user, a Minerbot infection manifests as extreme system sluggishness, loud laptop fans, and battery drain, even when the computer is idle. For a security analyst, it represents a breach of network integrity and a significant financial drain. Unlike ransomware, which announces its presence, Minerbots strive for absolute stealth, aiming to mine indefinitely without detection.

Execution and Mining Mechanics
Minerbots are distributed via a wide variety of vectors, including malspam (`T1566.001`), exploit kits, and frequently by exploiting unpatched public-facing vulnerabilities (like Apache Log4j or vulnerable web servers) (`T1190`). Upon execution, the malware establishes persistence (often via Scheduled Tasks) (`T1053.005`) and downloads a specialized mining payload, frequently a modified version of the open-source XMRig miner. To evade detection, the malware injects the mining code into legitimate processes like `svchost.exe` or `notepad.exe` (`T1055`). Advanced variants monitor task manager execution; if the user opens Task Manager, the miner temporarily pauses to hide the CPU spike (`T1562.001`). The bot communicates with a mining pool via the Stratum protocol (often over TCP port 3333 or 14444) to receive hashing work and submit completed shares (`T1071`).

Indicators of Compromise & Impact
The primary impact is resource exhaustion, hardware degradation, and increased operational costs. The most prominent host-based IoC is a sustained 100% CPU or GPU utilization by an unusual or injected process (like `svchost.exe` running under a user context instead of SYSTEM). Network analysts should look for sustained outbound traffic using the Stratum protocol to known cryptocurrency mining pools (e.g., MineXMR, SupportXMR).

MITRE ATT&CK Techniques

Observed techniques used by this family, mapped to the MITRE ATT&CK framework:

Tactical Mitigations

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

• T1071: Monitor network traffic for anomalous application layer protocols like non-standard HTTP/S patterns or unexpected DNS requests.

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_MINERBOT {
    meta:
        description = "Detects Minerbot (ransomware)"
        author = "SystemHelpdesk Boilerplate Generator"
        date = "2026-07-06"
    strings:
        $s1 = "minerbot" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

Sigma Rule

title: Suspicious Minerbot Activity
id: 2bf6ca9b52f46c1f80876f3367858055
status: experimental
description: Detects generic indicators of the minerbot malware family.
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith:
            - '\cmd.exe'
            - '\powershell.exe'
        CommandLine|contains:
            - "*minerbot*"
    condition: selection
level: medium

Containment & Response Steps

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

1. Isolate the endpoint to sever the connection to the mining pool, which immediately halts the generation of revenue for the attacker.
2. Use EDR to identify and terminate the heavily obfuscated or injected process consuming the CPU resources.
3. Remove the persistence mechanisms (Registry keys or Scheduled Tasks) used to launch the miner.
4. Block known mining pool domains and standard Stratum protocol ports at the enterprise firewall.

What to Avoid

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

1. Do not ignore a Minerbot infection just because it isn't ransomware; the vector used to deploy the miner (e.g., an unpatched vulnerability) can easily be used to deploy ransomware next.
2. Avoid relying solely on CPU monitoring for detection, as advanced miners throttle their usage to stay below alerting thresholds.

References & External Analysis

• Search "minerbot" on VirusTotal (External Analysis)

Frequently Asked Questions

Related Families (Category: ransomware)

Explore other malware families in the same category:

• Fuerboos
• Adwaresig
• Frethoq
• Schwarzesonne
• Imali

Machine-readable

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