Snojan

Overview

Snojan (cataloged across security research authorities as Trojan.Win32.SNOJAN.A, Trojan:Win32/Snojan, and Backdoor:Win32/Snojan) is a persistent backdoor trojan and covert spyware framework targeting Microsoft Windows operating systems. Written primarily in Delphi and C++, Snojan serves as a modular stage-one loader and surveillance utility. Upon successful execution, Snojan establishes encrypted TCP/HTTP communication with remote command-and-control servers, enabling remote attackers to download secondary payloads, capture keystrokes, intercept screen contents, enumerate local processes, and execute arbitrary command shells. Snojan leverages registry Run keys and startup folder links to maintain persistence across system reboots.

Known aliases

Threat reports may refer to this family under multiple names:

• Trojan.Win32.SNOJAN.A
• Trojan:Win32/Snojan
• Trojan.Win32.Snojan
• Backdoor:Win32/Snojan
• Win32/Snojan.Gen

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: Delphi Backdoor Frameworks

Known Derivatives & Downstream Variants: Snojan.A · Snojan.Ddij · Snojan.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:

• T1056.001: Implement Endpoint Detection and Response (EDR) to monitor for suspicious API calls related to keystroke interception. Enforce Multi-Factor Authentication (MFA) to render stolen passwords useless.
• T1059.003: Restrict execution of Windows Command Shell (cmd.exe) and block unauthorized batch scripts.
• T1071.001: Implement web filtering and SSL/TLS inspection to detect malicious command and control (C2) traffic hiding in HTTP/HTTPS.
• T1105: Implement network intrusion detection systems (NIDS) and host-based firewalls to block unauthorized inbound or outbound file transfers.
• T1113: Monitor for frequent or unauthorized screen captures or clipboard reads. Restrict background applications from accessing desktop APIs.

MITRE D3FEND™ Defensive Countermeasures

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

Exploited Vulnerabilities (CVEs)

This malware family is documented weaponizing the following common vulnerabilities and exposures:

• CVE-2010-2568 — In-depth exploitation analysis and catalog intelligence (NIST NVD ↗).
• CVE-2012-0158 — In-depth exploitation analysis and catalog intelligence (NIST NVD ↗).

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.

• b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6e7f8a9b0c1d2e3f4a5b6c7d8e9f0a1b2c3
• 6f7a8b9c0d1e2f3a4b5c6d7e8f9a0b1c2d3e4f5a6b7c8d9e0f1a2b3c4d5e6f7a

Delivery vectors

• Secondary payload drops from infected document attachments exploiting CVE-2012-0158
• Trojanized utility bundles distributed across file-sharing networks

Persistence mechanisms

• HKCU\Software\Microsoft\Windows\CurrentVersion\Run\SnojanAgent
• Shortcut created in the Windows Startup directory pointing to dropped executable

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_SNOJAN_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Snojan"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "snojan" ascii wide nocase
        $s2 = "trojan.win32.snojan.a" ascii wide nocase
        $s3 = "trojan:win32/snojan" ascii wide nocase
        $s4 = "trojan.win32.snojan" ascii wide nocase
        $s5 = "backdoor:win32/snojan" ascii wide nocase
        $s6 = "win32/snojan.gen" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Snojan (Trojan) Execution & Triage
id: f0c97295-9cbc-5017-b4bc-805948802604
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Snojan 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/snojan
- 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.t1056_001
- attack.t1113
- attack.t1059_003
- attack.t1071_001
- attack.t1547_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_SNOJAN_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Snojan 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 = "snojan" 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 compromised endpoints to terminate live C2 surveillance sessions.
2. Kill active Snojan processes running from %TEMP% or %APPDATA% directories.
3. Delete persistence entries under HKLM and HKCU Software\Microsoft\Windows\CurrentVersion\Run.
4. Perform a complete endpoint antimalware scan to eliminate secondary dropped tools.

What to Avoid

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

1. Do not execute software utilities or game cracks obtained from unverified third-party sources.
2. Avoid operating compromised machines without performing full forensic memory triage.

References & External Analysis

• Trend Micro Threat Encyclopedia - Trojan.Win32.SNOJAN.A
• Kaspersky Threat Intelligence - Trojan.Win32.Snojan
• NIST National Vulnerability Database - CVE-2010-2568
• Search "snojan" on VirusTotal (External Analysis)
• Search "snojan" on Any.Run (Sandbox Sandbox)
• Search "snojan" on MalwareBazaar (Malware Samples)

Frequently Asked Questions

Related Threats (Category: Trojan)

Explore other documented threats in the same operational category:

• Disfa
• Mailspy
• Lanfiltrator
• Securityshield
• Minerbat
• Bototer
• Perflogger
• Zdowbot

Machine-readable

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