Cryptominer

Overview

Executive Summary

Technical Architecture and Capabilities

• Resource Exhaustion: The primary signature of a cryptominer is the immediate, sustained maximization of CPU or GPU usage. The malware is designed to push the hardware to its thermal limits to generate cryptocurrency as rapidly as possible.
• Pool Communication: Miners do not operate in isolation; they connect to "Mining Pools" using the Stratum protocol (often over standard HTTP/HTTPS ports or custom TCP ports) to receive work algorithms and submit computed hashes.
• Defense Evasion: Advanced miners (like those deployed by the LemonDuck botnet) contain routines to monitor for the execution of Task Manager or Resource Monitor. If the user attempts to check system performance, the miner will temporarily pause its operations to hide the CPU spike.

Threat Impact

Incident Response and Advanced Analysis

• Performance Monitoring: Utilize enterprise monitoring tools to identify endpoints exhibiting sustained, unexplained 100% CPU/GPU utilization during normal business hours.
• Network Blocking: Identify and block network connections to known mining pool domains (e.g., `minexmr.com`, `nanopool.org`) at the corporate firewall to immediately render the miners useless.
• Eradication: Isolate the endpoint and perform a deep system scan to remove the miner executable, its associated persistence mechanisms (Registry `Run` keys, WMI subscriptions), and any secondary backdoors dropped by the initial infection vector.

Known aliases

Threat reports may refer to this family under multiple names:

• Riskware.CoinMiner
• Trojan.Miner
• PUA.Miner

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:

• T1059: Restrict execution of scripting languages such as PowerShell, VBScript, or Python to authorized administrators. Enforce Script Block Logging.

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_CRYPTOMINER_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Cryptominer"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "cryptominer" ascii wide nocase
        $s2 = "riskware.coinminer" ascii wide nocase
        $s3 = "trojan.miner" ascii wide nocase
        $s4 = "pua.miner" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Cryptominer (Trojan) Execution & Triage
id: 3af6d3ea-3c7d-5428-b10d-e62eaae01ea0
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Cryptominer 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/cryptominer
- 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.t1496
- attack.t1059
- attack.t1562_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_CRYPTOMINER_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Cryptominer 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 = "cryptominer" 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. Sever network connectivity for the flagged endpoint to terminate persistent command-and-control (C2) communication channels and stop Cryptominer from retrieving secondary stage payloads.
2. Capture process memory triage to detect and terminate malicious threads injected by Cryptominer into legitimate system processes such as explorer.exe or svchost.exe.
3. Audit Windows Registry Run keys (HKCU\Software\Microsoft\Windows\CurrentVersion\Run) and Task Scheduler entries to locate and purge Cryptominer persistence hooks.
4. Deploy updated enterprise EDR detection signatures and conduct an out-of-band endpoint scan to isolate dropped binaries and staged payloads.
5. Rotate all credentials, domain user passwords, and session cookies active on the system during the Cryptominer execution timeframe.

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 incident is resolved simply because an antivirus tool removed the initial Cryptominer dropper; always verify that secondary payloads and persistence hooks have been eradicated.
2. Avoid logging in with Domain Admin or privileged credentials on a machine suspected of running Cryptominer until memory triage is complete.
3. Do not delay host isolation; automated lateral movement and credential dumping can occur within minutes of initial execution.

References & External Analysis

• Search "cryptominer" on VirusTotal (External Analysis)
• Search "cryptominer" on Any.Run (Sandbox Sandbox)
• Search "cryptominer" on MalwareBazaar (Malware Samples)

Frequently Asked Questions

Related Threats (Category: Trojan)

Explore other documented threats in the same operational category:

• Guagua
• Webbrowserpassview
• Xxybwe
• Zdowbot
• Adwind
• Bobax
• Delfinject
• Wakme

Machine-readable

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