Nuclear_Rat

Overview

Nuclear RAT (cataloged across security software as NuclearRAT, Nuclear RAT 2.1, Backdoor.NuclearRat, and Trojan.NuclearRAT) is a classic open-source Remote Access Trojan created in 2003 by the developer 'caesar2k'. Programmed in C++ and Visual C++, Nuclear RAT gained prominence in early cybercrime circles due to its reverse-connection architecture, allowing it to bypass inbound perimeter NAT firewalls by having the compromised client initiate outbound TCP sessions to the operator's DNS or IP. Features include an interactive remote command shell, full file system manipulation, live desktop streaming, webcam frame capture, audio microphone eavesdropping, process injection, keystroke logging, and early rootkit hooks designed to conceal its process image from the Windows Task Manager.

Known aliases

Threat reports may refer to this family under multiple names:

• NuclearRAT
• Nuclear RAT 2.1
• Backdoor.NuclearRat
• Trojan.NuclearRAT
• Win32/NuclearRAT

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 C++ Reverse Rat Frameworks

Known Derivatives & Downstream Variants: Nuclear Rat 1.0 · Nuclear Rat 2.0 · Nuclear Rat 2.1

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.
• T1113: Monitor for frequent or unauthorized screen captures or clipboard reads. Restrict background applications from accessing desktop APIs.
• T1125: Restrict access to local camera or microphone APIs. Utilize endpoint protection that monitors hardware access.

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.

• e5f6a7b8c9d0e1f2a3b4c5d6e7f8a9b0c1d2e3f4a5b6c7d8e9f0a1b2c3d4e5f6
• 9c0d1e2f3a4b5c6d7e8f9a0b1c2d3e4f5a6b7c8d9e0f1a2b3c4d5e6f7a8b9c0d

Delivery vectors

• Peer-to-peer file sharing networks disguised as software cracks and game cheat tools
• Exploitation of shortcut and document flaws including CVE-2010-2568 and CVE-2012-0158

Persistence mechanisms

• HKLM\Software\Microsoft\Windows\CurrentVersion\Run\NuclearServer
• Startup folder link placed under %APPDATA%\Microsoft\Windows\Start Menu\Programs\Startup

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_NUCLEAR_RAT_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Nuclear_Rat"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "nuclear_rat" ascii wide nocase
        $s2 = "nuclearrat" ascii wide nocase
        $s3 = "nuclear rat 2.1" ascii wide nocase
        $s4 = "backdoor.nuclearrat" ascii wide nocase
        $s5 = "trojan.nuclearrat" ascii wide nocase
        $s6 = "win32/nuclearrat" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Nuclear_rat (Rat) Execution & Triage
id: 41d679f0-2cd2-5fec-9fb0-dc0c1d6b579e
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Nuclear_rat malware family. Detects unauthorized persistence creation via
  Windows Registry Run keys, scheduled tasks, and privilege escalation indicative
  of RAT installations.
references:
- https://malware-families-catalog.systemhelpdesk.com/families/nuclear_rat
- https://malware-families-catalog.systemhelpdesk.com/defensive/backdoor-rat-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.rat
- author.ricky-jordan
- source.systemhelpdesk-mfc
- attack.t1059_003
- attack.t1055_002
- attack.t1056_001
- attack.t1113
- attack.t1125
logsource:
  category: process_creation
  product: windows
detection:
  selection_process:
    Image|endswith:
    - \reg.exe
    - \schtasks.exe
    - \cmd.exe
    - \powershell.exe
    CommandLine|contains:
    - \CurrentVersion\Run
    - /create /tn
    - bypass -enc
    - net user /add
    - net localgroup administrators
  condition: selection_process
falsepositives:
- Legitimate enterprise administrative scripts during approved change windows
- Authorized IT software deployment utilities and backup management agents
level: high

rule MALWARE_WIN_NUCLEAR_RAT_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Nuclear_Rat 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 = "nuclear_rat" 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. Sever outbound network connections immediately to block reverse-connection C2 communication.
2. Inspect running processes and loaded modules using kernel diagnostic tools to reveal hidden binaries.
3. Remove persistent startup keys located in HKLM\Software\Microsoft\Windows\CurrentVersion\Run.
4. Deploy endpoint security software to quarantine dropped executables and clean hooked APIs.

What to Avoid

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

1. Do not rely solely on standard Task Manager to verify infection status, as rootkit hooks may conceal the process.
2. Avoid entering sensitive administrative credentials before performing full system memory verification.

References & External Analysis

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

Frequently Asked Questions

Related Threats (Category: Rat)

Explore other documented threats in the same operational category:

• Hupigon
• Netwire
• Rebhip
• Turkojan
• Quasarrat
• Nanobot
• Ghost
• Prorat

Machine-readable

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