Xorist

Overview

Xorist (classified across the cybersecurity industry as Ransom:Win32/Xorist, Trojan-Ransom.Win32.Xorist, and Enigma/Xorist builder family) is a landmark, highly configurable ransomware construction kit active since 2010. Developed in Delphi/C++, the Xorist ransomware builder allows novice threat actors to generate customized ransomware binaries with configurable file extension targets, custom ransom note texts, and extortion demands via SMS or cryptocurrency. Xorist encrypts files using symmetric XOR, TEA (Tiny Encryption Algorithm), or AES algorithms, appending custom extensions (such as .xorist, .EnCiPhErEd, or user-defined strings) to encrypted files. Xorist displays a modal lock screen, disables Task Manager, and deletes Volume Shadow Copies. Because early builders used weak XOR keys or deterministic PRNGs, antimalware vendors and Kaspersky developed universal decryption tools for many Xorist variants.

Known aliases

Threat reports may refer to this family under multiple names:

• Ransom:Win32/Xorist
• Trojan-Ransom.Win32.Xorist
• Win32/Xorist
• Xorist Ransomware Builder
• Trojan-Ransom.Win32.Enigma

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_XORIST_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Xorist"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "xorist" ascii wide nocase
        $s2 = "ransom:win32/xorist" ascii wide nocase
        $s3 = "trojan-ransom.win32.xorist" ascii wide nocase
        $s4 = "win32/xorist" ascii wide nocase
        $s5 = "xorist ransomware builder" ascii wide nocase
        $s6 = "trojan-ransom.win32.enigma" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Xorist (Ransomware) Execution & Triage
id: f8d3fe00-6986-5940-95fe-a4807bbb2229
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Xorist 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/xorist
- 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.t1486
- attack.t1491
- attack.t1490
- attack.t1562_001
- attack.t1547_001
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_XORIST_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Xorist 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 = "xorist" 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 endpoint from the network to prevent the ransomware from enumerating and encrypting shared network drives (SMB shares).
2. Identify the specific variant and extension used; check the 'No More Ransom' project, as decryption tools are freely available for many older Xorist iterations.
3. Use EDR or Process Explorer to terminate the active encryption process before attempting to clean the Registry Run keys.
4. If decryption is impossible, restore the affected files from a secure, offline backup after a complete OS rebuild.

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; due to the amateur nature of many Xorist operators, paying does not guarantee you will receive a working decryption key.
2. Avoid restarting the computer if the encryption process is actively running, as this can corrupt files currently being processed.

References & External Analysis

• Microsoft Defender Threat Encyclopedia - Ransom:Win32/Xorist
• Kaspersky Threat Intelligence - Trojan-Ransom.Win32.Xorist Analysis
• MITRE ATT&CK - Data Encrypted for Impact (T1486)
• Search "xorist" on VirusTotal (External Analysis)
• Search "xorist" on Any.Run (Sandbox Sandbox)
• Search "xorist" on MalwareBazaar (Malware Samples)

Frequently Asked Questions

Related Threats (Category: Ransomware)

Explore other documented threats in the same operational category:

• Gaofenq
• Purga
• Ploprolo
• Banz
• Genericrxfs
• Leymo
• Zbiw
• Black

Machine-readable

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