Immirat

Overview

Immirat (classified across cybersecurity vendors as Trojan:Win32/Immirat, Backdoor:Win32/Immirat, and Trojan.Generic.Immirat) is a sophisticated remote access trojan (RAT) and backdoor targeting Microsoft Windows operating systems. Derived from modular commercial surveillance and crimeware frameworks, Immirat provides malicious operators with total interactive remote management over compromised endpoints. Upon execution, the malware establishes persistent registry Run keys under HKCU\Software\Microsoft\Windows\CurrentVersion\Run and creates disguised background tasks. It initializes an encrypted TCP socket channel with remote command-and-control (C2) servers to receive operator instructions. Immirat is equipped with comprehensive surveillance modules including live remote desktop streaming, microphone and webcam capture, low-level keystroke logging, clipboard interception, and automated credential harvesting from web browsers and email clients. Furthermore, the backdoor supports arbitrary file upload and download, remote process injection into svchost.exe, command shell execution, and the ability to drop secondary ransomware or cryptocurrency mining payloads.

Known aliases

Threat reports may refer to this family under multiple names:

• Trojan:Win32/Immirat
• Backdoor:Win32/Immirat
• Win32/Immirat
• ImmiRAT
• Trojan.Immirat

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.
• 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):

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_IMMIRAT_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Immirat"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "immirat" ascii wide nocase
        $s2 = "trojan:win32/immirat" ascii wide nocase
        $s3 = "backdoor:win32/immirat" ascii wide nocase
        $s4 = "win32/immirat" ascii wide nocase
        $s5 = "immirat" ascii wide nocase
        $s6 = "trojan.immirat" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Immirat (Rat) Execution & Triage
id: 806a735a-2f82-5250-adb0-3d09f59ae390
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Immirat 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/immirat
- 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
- 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_IMMIRAT_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Immirat 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 = "immirat" 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; an active, human adversary is likely controlling the machine in real-time.
2. Assume all local credentials and session tokens on the machine have been compromised and initiate enterprise-wide password resets.
3. Capture a forensic memory image (RAM dump) to extract the decrypted C2 configuration and analyze any active reverse shell connections.
4. Hunt for lateral movement originating from the infected machine by analyzing Windows Event Logs (e.g., Event ID 4624 for successful network logons).

What to Avoid

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

1. Do not simply delete the RAT executable and leave the machine on the network; the attacker may have already established secondary backdoors or compromised other hosts.
2. Avoid relying solely on static AV scans, as RATs frequently update their payloads and inject into memory to evade file-based detection.

References & External Analysis

• Microsoft Defender Threat Encyclopedia - Trojan:Win32/Immirat
• Trend Micro Threat Intelligence Encyclopedia - Trojan.Win32.IMMIRAT
• MITRE ATT&CK - Remote Access Software & Backdoor Techniques
• Search "immirat" on VirusTotal (External Analysis)
• Search "immirat" on Any.Run (Sandbox Sandbox)
• Search "immirat" on MalwareBazaar (Malware Samples)

Frequently Asked Questions

Related Threats (Category: Rat)

Explore other documented threats in the same operational category:

• Apocalypse_Rat
• Quasar
• Cybergate
• Houndhack
• Bladabindi
• Netwiredrc
• Zegost
• Netwire

Machine-readable

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