Snare

Overview

Backdoor:Win32/Snare is a stealthy remote access trojan (RAT) or backdoor designed to provide threat actors with persistent, undetected, and interactive access to a compromised network. It allows attackers to exfiltrate data, monitor user activity, and deploy additional malware payloads on demand.

Understanding Snare
To a victim, a Snare infection is completely silent. For a SOC analyst, Snare represents a critical breach involving 'hands-on-keyboard' access. Once deployed, the attacker can seamlessly traverse the network, steal high-value credentials, exfiltrate sensitive data, and deploy further destructive payloads, all while appearing as legitimate background system activity.

Execution, Evasion, and Interactive Control
Snare is typically deployed by initial access brokers, dropped via exploit kits, or executed through macro-enabled spear-phishing documents (`T1566.001`). Upon execution, it heavily relies on Process Injection or Process Hollowing (`T1055`), often unpacking its payload directly into the memory space of a legitimate process like `svchost.exe`. It establishes persistence via hidden Registry keys or Services (`T1543.003`). The backdoor provides a massive suite of capabilities: live keylogging, password recovery, remote command execution (`T1059`), and the ability to seamlessly download and execute secondary malware (`T1105`). Snare often uses customized, encrypted protocols for its C2 communications to evade network IDS (`T1071.001`).

Indicators of Compromise & Impact
The impact is total endpoint compromise and the high probability of lateral movement across the enterprise. Host-based IoCs require careful EDR monitoring: look for legitimate system processes initiating outbound, encrypted network connections to unknown IP addresses, or anomalous child processes spawning from `explorer.exe`. Memory analysis is almost always required to locate the unencrypted Snare payload residing in hollowed memory segments.

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.
• T1071.001: Implement web filtering and SSL/TLS inspection to detect malicious command and control (C2) traffic hiding in HTTP/HTTPS.

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_SNARE_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Snare"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "snare" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Snare (Trojan) Execution & Triage
id: 04956b67-c6f3-55a2-a842-d8af2faa33c7
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Snare 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/snare
- 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.t1059
- attack.t1071_001
- attack.t1055
- attack.t1543_003
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_SNARE_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Snare 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 = "snare" 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. Immediately isolate the infected endpoint from the network to sever the attacker's interactive control session and halt lateral movement.
2. Assume all credentials typed on the machine or stored locally have been stolen, and mandate immediate enterprise-wide password resets for the affected user.
3. Perform a deep memory forensics analysis to extract the Snare payload and determine its exact C2 infrastructure for network-wide blocking.
4. Do a thorough hunt across the environment for lateral movement, as the attacker likely used the backdoor to compromise file shares or domain controllers.

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 attack is thwarted if an AV engine quarantines a dropper; the Snare backdoor itself may already be running resident in memory.
2. Avoid rebooting the machine before capturing a memory image, as the decrypted payload and critical forensic evidence will be lost.

References & External Analysis

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

Frequently Asked Questions

Related Threats (Category: Trojan)

Explore other documented threats in the same operational category:

• Ulise
• Winevar
• Informer
• Ymkfawdgfnmi
• Dapato
• Joker
• Mapstosteal
• Imminent

Machine-readable

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