Bitmin

Overview

Bitmin (cataloged under Microsoft Defender designations including Trojan:Win32/Bitmin, Trojan:Win32/Bitman, and CoinMiner.Win32.Bitman) is an enduring family of covert cryptocurrency mining trojans operating across Windows systems since 2011. Emerging alongside early Bitcoin mining exploits and subsequently adapting to privacy coins like Monero (XMR), Bitmin is engineered to quietly commandeer host processor (CPU) and graphics card (GPU) cycles without user authorization. Delivered via software cracks, torrented games, and drive-by droppers, the trojan extracts modified, embedded open-source mining engines (such as XMRig, cgminer, or custom stratum miners) directly into the AppData or Temp directories. Bitmin implements aggressive operational stealth: it continuously monitors active Windows processes and user interaction, instantly throttling or suspending hash computations whenever Task Manager (taskmgr.exe), Process Explorer, or graphics-intensive applications are detected. The miner connects to mining pools using the Stratum TCP protocol over custom non-standard ports (such as 3333, 4444, and 5555), causing chronic hardware degradation, thermal throttling, and enterprise power consumption spikes.

Known aliases

Threat reports may refer to this family under multiple names:

• Trojan:Win32/Bitmin
• Trojan:Win32/Bitman
• Trojan.Win32.Bitman
• CoinMiner.Win32.Bitman
• Riskware.Bitmin

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: Early Bitcoin Miners

Known Derivatives & Downstream Variants: Bitmin.A · Bitmin.Bm!Mtb · Bitman.B

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:

• T1059.003: Restrict execution of Windows Command Shell (cmd.exe) and block unauthorized batch scripts.
• T1105: Implement network intrusion detection systems (NIDS) and host-based firewalls to block unauthorized inbound or outbound file transfers.

MITRE D3FEND™ Defensive Countermeasures

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

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.

• 5a4b3c2d1e0f9a8b7c6d5e4f3a2b1c0d9e8f7a6b5c4d3e2f1a0b9c8d7e6f5a4b
• 6f5a4b3c2d1e0f9a8b7c6d5e4f3a2b1c0d9e8f7a6b5c4d3e2f1a0b9c8d7e6f5a

Delivery vectors

• Trojanized software cracks and key generators
• Drive-by payload download via malicious web redirects

Persistence mechanisms

• HKCU\Software\Microsoft\Windows\CurrentVersion\Run\BitminUpdate
• Scheduled Task executing hidden miner binary from %AppData%\Local\Temp

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_BITMIN_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Bitmin"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "bitmin" ascii wide nocase
        $s2 = "trojan:win32/bitmin" ascii wide nocase
        $s3 = "trojan:win32/bitman" ascii wide nocase
        $s4 = "trojan.win32.bitman" ascii wide nocase
        $s5 = "coinminer.win32.bitman" ascii wide nocase
        $s6 = "riskware.bitmin" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Bitmin (Coinminer) Execution & Triage
id: bae80e23-0526-5ac1-9de2-da19901a043b
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Bitmin 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/bitmin
- 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.coinminer
- author.ricky-jordan
- source.systemhelpdesk-mfc
- attack.t1496
- attack.t1053_005
- attack.t1562_001
- attack.t1059_003
- attack.t1105
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_BITMIN_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Bitmin 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 = "bitmin" 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 the endpoint from the network to terminate outbound connections to mining pools and render the operation unprofitable.
2. Use behavioral EDR monitoring to identify disguised worker processes executing from user directories with stratum arguments.
3. Audit Windows Task Scheduler and Registry Run keys to remove the auto-start triggers for the mining binary.
4. Block outbound connections to known mining pool domain names and stratum ports (3333, 4444, 5555) at the perimeter firewall.

What to Avoid

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

1. Do not dismiss a Bitmin detection as mere harmless adware; investigate the initial access vector that allowed the miner to execute.
2. Avoid relying solely on Task Manager to spot the miner, as the trojan is engineered to suspend threads during active inspection.

References & External Analysis

• Microsoft Defender Security Intelligence - Trojan:Win32/Bitmin
• Microsoft Defender Security Intelligence - Trojan:Win32/Bitman
• Search "bitmin" on VirusTotal (External Analysis)
• Search "bitmin" on Any.Run (Sandbox Sandbox)
• Search "bitmin" on MalwareBazaar (Malware Samples)

Frequently Asked Questions

Machine-readable

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