Donex

Overview

Ransom:Win32/Donex is a destructive ransomware family that targets both individual users and enterprise networks, utilizing strong cryptographic algorithms to encrypt valuable files and demand payment for their release. Like many modern ransomware variants, it is designed to cause maximum operational disruption to force swift payment from the victim.

Understanding Donex Ransomware
To an infected user, the outcome is catastrophic: documents, databases, and critical files are suddenly inaccessible, their filenames often appended with a specific extension. A ransom note (usually an HTML or TXT file dropped in every directory) demands cryptocurrency. For a security operations center (SOC), a Donex detonation often represents the final stage of a prolonged network compromise, indicating that attackers have successfully bypassed endpoint defenses and potentially moved laterally across the network.

Execution and Encryption Mechanics
Donex is distributed via various vectors, including spear-phishing (`T1566`), malicious spam attachments, or manually deployed by attackers via compromised Remote Desktop Protocol (RDP) (`T1133`). Upon execution (`T1204.002`), it often attempts to terminate critical database and backup services (like SQL Server or Veeam) (`T1489`) to ensure those files are unlocked and vulnerable. It executes commands to delete Windows Volume Shadow Copies (`T1490`) using `vssadmin.exe` to prevent easy restoration. It then traverses the file system and mapped network drives, encrypting files using strong cryptography (`T1486`).

Indicators of Compromise & Impact
The impact is severe operational downtime and potential permanent data loss. The primary IoC is the massive, rapid modification of files across the hard drive and network shares. Host-based IoCs include EDR alerts for the mass deletion of shadow copies (`vssadmin delete shadows`) and the sudden termination of critical services. Network logs may show the initial command-and-control (C2) check-in to exchange the public encryption keys.

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):

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_DONEX_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Donex"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "donex" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Donex (Ransomware) Execution & Triage
id: 0692d0fc-9388-5ba8-8da0-051141263ef3
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Donex malware family. Detects volume shadow copy deletion, boot status
  tampering, and recovery inhibition characteristic of modern ransomware operations.
references:
- https://malware-families-catalog.systemhelpdesk.com/families/donex
- 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.ransomware
- author.ricky-jordan
- source.systemhelpdesk-mfc
- attack.t1489
- attack.t1490
- attack.t1204_002
- attack.t1486
logsource:
  category: process_creation
  product: windows
detection:
  selection_process:
    Image|endswith:
    - \vssadmin.exe
    - \wmic.exe
    - \wbadmin.exe
    - \bcdedit.exe
    CommandLine|contains:
    - delete shadows
    - shadowcopy delete
    - resize shadowstorage
    - recoveryenabled no
    - ignoreallfailures
  condition: selection_process
falsepositives:
- Legitimate enterprise administrative scripts during approved change windows
- Authorized IT software deployment utilities and backup management agents
level: critical

rule MALWARE_WIN_DONEX_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Donex 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 = "donex" 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. Instantly isolate the infected endpoint from the network to halt the encryption process, explicitly disconnecting it from mapped network shares.
2. Do NOT reboot the machine immediately; capture a live memory dump (RAM) first, as forensic analysis may recover the encryption keys from memory.
3. Check for publicly available decryption tools on 'No More Ransom'; some older ransomware variants have known cryptographic flaws.
4. Wipe the infected systems and restore data from secure, immutable offline backups.

What to Avoid

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

1. Do not pay the ransom. Paying funds criminal enterprises, and there is no guarantee the attackers will provide a working decryption tool.
2. Avoid reconnecting the machine to the network until a full forensic investigation has identified the initial entry vector (e.g., compromised RDP).

References & External Analysis

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

Frequently Asked Questions

Related Threats (Category: Ransomware)

Explore other documented threats in the same operational category:

• Batton
• Mbrlock
• Asym
• Sakto
• Sinresby
• Phnu
• Blueh
• Desurou

Machine-readable

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