Njrat

Overview

njRAT (also tracked as Bladabindi, Njw0rm, and Backdoor:MSIL/Bladabindi) is a notorious, widely disseminated remote access trojan (RAT) developed in Microsoft Visual Basic .NET by a Kuwaiti threat actor known as 'njq8'. First surfacing in 2012 and publicly distributed across underground forums, njRAT became one of the most widespread commodity remote administration tools in the Middle East and worldwide. njRAT establishes persistent reverse TCP socket connections to operator command-and-control servers, utilizing dynamic DNS domains and communicating via custom plaintext protocols delimited by the string '|'|'|'. The trojan provides operators with extensive interactive surveillance and administrative control: it features real-time keystroke logging via the GetAsyncKeyState Windows API, live desktop screen streaming, webcam and microphone spying, arbitrary process execution via cmd.exe and PowerShell, file system manipulation, and automated credential theft from web browsers, FileZilla, and instant messaging clients. To evade detection, njRAT executes process hollowing (T1055.012) into trusted Windows processes (such as svchost.exe), modifies firewall rules via netsh, and adds itself to registry autostart keys. In June 2014, Microsoft and the FBI executed a landmark civil and criminal operation, seizing 22 dynamic DNS domains managed by No-IP (Vitalwerks) that were actively facilitating njRAT and Bladabindi botnets, accompanied by CISA Alert AA14-143A.

Known aliases

Threat reports may refer to this family under multiple names:

• Bladabindi
• Njw0rm
• Backdoor:MSIL/Bladabindi
• Trojan.MSIL.njRAT
• Win32/Bladabindi

Family Pedigree & Lineage

Malware authors regularly fork and iterate upon existing codebases. Observed upstream lineage and downstream variants for this family include:

Known Derivatives & Downstream Variants: Njrat_V0.7D · Njw0Rm · Bladabindi

MITRE ATT&CK Techniques

This family has been observed using the following ATT&CK techniques: T1056.001 · T1113 · T1125 · T1123 · T1059.003 · T1071.001 · T1547.001 · T1555.003 · T1055.012

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-2017-11882 — 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.

• 4ffc186835a74659f170423c91465d3ec62b1e7c53d51786ce45464fb5f4581d
• 1bc7ee24bf3692e8fa4c3f56ebc5970c40cebf656a1bce47b74f391152a4e98f

Delivery vectors

• Malicious spam emails delivering weaponized Office documents exploiting CVE-2017-11882
• Spear-phishing archives with embedded LNK shortcuts or executable screensavers (.scr)
• P2P file sharing networks hosting cracked software and keygens bundled with njRAT

Persistence mechanisms

• HKCU\Software\Microsoft\Windows\CurrentVersion\Run entry pointing to dropped .NET executable
• Startup folder shortcut under %APPDATA%\Microsoft\Windows\Start Menu\Programs\Startup
• Process injection into svchost.exe to conceal running processes

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_NJRAT_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Njrat"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "njrat" ascii wide nocase
        $s2 = "bladabindi" ascii wide nocase
        $s3 = "njw0rm" ascii wide nocase
        $s4 = "backdoor:msil/bladabindi" ascii wide nocase
        $s5 = "trojan.msil.njrat" ascii wide nocase
        $s6 = "win32/bladabindi" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Njrat (Rat) Execution & Triage
id: 7400cf07-bd99-5283-9bf8-80efd40c70a8
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Njrat 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/njrat
- 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.t1056_001
- attack.t1113
- attack.t1125
- attack.t1123
- attack.t1059_003
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_NJRAT_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Njrat 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 = "njrat" 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
}

References & External Analysis

• CISA Alert AA14-143A: Technical Analysis of njRAT and Bladabindi
• Microsoft On the Issues: Cracking Down on Malicious Dynamic DNS Infrastructure
• Trend Micro: Dissecting the njRAT Remote Access Trojan
• CISA Advisory: AA14-143A
• Search "njrat" on VirusTotal (External Analysis)
• Search "njrat" on Any.Run (Sandbox Sandbox)
• Search "njrat" on MalwareBazaar (Malware Samples)

North American Authority Advisory (CISA / NIST)

The Cybersecurity and Infrastructure Security Agency (CISA) has published an official US federal advisory on this family, which can be mapped to NIST Cybersecurity Framework (CSF) incident response controls: AA14-143A ↗

Frequently Asked Questions

Related Threats (Category: Rat)

Explore other documented threats in the same operational category:

• Poison
• Hav_Rat
• Lost_Door
• Farfli
• Nanobot
• Quasarrat
• Ghost
• Rescoms

Machine-readable

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