Serenity_Rat

Category: rat · Aliases: Serenity RAT, Backdoor.Win32.Serenity, Serenity by Killua, Win32/Serenity.RAT, Trojan.Serenity · Sample count (EMBER 2018): 0 · Enrichment: curated_sourced · Updated: 2026-10-14
Category: RatSeverity: HIGHStatus: Automated SignaturePlatform: WINDOWS_PEStage: Initial Access, Execution, Command And ControlFirst seen: 2006Motivation: Espionage🕸 Explore Relationship Graph⚙ API JSON⚡ Sigma Rule💾 YARA RuleOS: Windows 11, Windows 10, Windows Server 2022
Executive Summary
Serenity RAT (cataloged across security software as Backdoor.Win32.Serenity, Trojan.Serenity, and Serenity RAT) is a mid-2000s Remote Access Trojan created in Borland Delphi by the Belgian developer known as 'Killua'.

Table of Contents

Overview

Serenity RAT (cataloged across security software as Backdoor.Win32.Serenity, Trojan.Serenity, and Serenity RAT) is a mid-2000s Remote Access Trojan created in Borland Delphi by the Belgian developer known as 'Killua'. Built with modularity and operator usability in mind, Serenity RAT offered a polished graphical control center for managing infected endpoints simultaneously. The server payload operated stealthily in the background, utilizing multithreaded socket listeners to handle real-time screen capture, remote file transfers, and registry browsing. Serenity RAT featured comprehensive keylogging capabilities with offline buffer storage, process injection, remote shell execution, and hardware enumeration. To maintain persistence, the server wrote autostart keys to the Windows Registry and could inject into explorer.exe. Distributed across underground forums, Serenity RAT droppers leveraged CVE-2010-2568 and CVE-2012-0158.

Known aliases

Threat reports may refer to this family under multiple names:

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 Rat Frameworks

Known Derivatives & Downstream Variants: Serenity Rat V1.0 · Serenity Rat V1.2

MITRE ATT&CK Techniques

Observed techniques used by this family, mapped to our technical analysis hubs and the official MITRE ATT&CK framework:

→ Explore the complete 226-Technique ATT&CK Threat Matrix

Tactical Mitigations

Based on the techniques used by this family, consider the following defensive strategies:

MITRE D3FEND™ Defensive Countermeasures

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

D3FEND IDCountermeasure NameTacticCountered ATT&CKDefensive Guidance
D3-PIADProcess Injection Analysis & DetectionDetectT1055.002Monitor cross-process thread creation (CreateRemoteThread) and asynchronous procedure calls (QueueUserAPC).
D3-MFAMulti-factor AuthenticationHardenT1056.001Enforce FIDO2 / WebAuthn physical tokens to render keystroke-intercepted passwords useless.
D3-PBAProcess Spawn AnalysisDetectT1059.003Inspect command-line arguments and anomalous parent-child relationships spawning from cmd.exe.
D3-WAFWeb Content Filtering & InspectionFilterT1071.001Block newly registered domains (NRDs) and inspect HTTP Host and URI headers for known C2 profiles.
D3-FDAFile Directory Access AuditingDetectT1083Audit and alert on high-frequency recursive directory queries executed by non-system and unclassified binaries.
D3-NTINetwork Traffic InspectionDetectT1105Inspect deep packet payloads for anomalous staging binaries and unauthorized egress protocols.
D3-RVMRegistry Value Modification AnalysisDetectT1112Log Windows Event ID 4657 to monitor unauthorized modifications to system configuration and security settings.
D3-RPMRegistry Persistence MonitoringDetectT1547.001Audit and restrict write privileges to user and machine-level Registry Run/RunOnce keys using Endpoint Privilege Management.

Exploited Vulnerabilities (CVEs)

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

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.

Delivery vectors

Persistence mechanisms

SIEM / EDR Ingestion: Need these reference indicators for threat hunting?

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:

Tier 1 Primitive Artifact Rule (Fast Triage)

Matches raw strings and file markers. Vulnerable to binary repacking and simple obfuscation.

rule MALWARE_WIN_SERENITY_RAT_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Serenity_Rat"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "serenity_rat" ascii wide nocase
        $s2 = "serenity rat" ascii wide nocase
        $s3 = "backdoor.win32.serenity" ascii wide nocase
        $s4 = "serenity by killua" ascii wide nocase
        $s5 = "win32/serenity.rat" ascii wide nocase
        $s6 = "trojan.serenity" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

Tier 2 Behavioral Context Rule (Process Chains & Sigma)

Tracks parent-child process anomalies and suspicious scripting telemetry. Resilient against file renames.

title: SystemHelpDesk Detection - Serenity_rat (Rat) Execution & Triage
id: 810e05c7-44e3-5c5a-b912-e5a6dada05ba
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Serenity_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/serenity_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.t1112
- attack.t1083
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

Tier 3 Attribution Fingerprint Rule (High Fidelity)

Deep signature matching distinctive operational fingerprints and payload characteristics.

rule MALWARE_WIN_SERENITY_RAT_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Serenity_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 = "serenity_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
}
SOC & SIEM Rule Downloads: ⬇ Download YARA Rule (.yar) ⬇ Download Sigma Rule (YAML) ⬇ Download Sigma Rule (JSON) ⚙ Threat Profile API (JSON)

Containment & Response Steps

Home Users: If you suspect a malware infection on your personal device, disconnect from the internet immediately and run a full system scan with your antivirus software (see our TotalAV Antivirus & Security Support Guide). The steps below are intended for IT professionals responding to enterprise incidents.

Ordered checklist for responders. Adapt to your environment and engage professional support for active incidents.

  1. Disconnect the affected endpoint from the local network to terminate active C2 control channels.
  2. Inspect explorer.exe and active process trees for injected backdoor DLLs or unmapped memory regions.
  3. Remove persistent startup entries in HKLM\Software\Microsoft\Windows\CurrentVersion\Run.
  4. Deploy endpoint security tools to scan for and eliminate dropped payloads and registry modifications.

What to Avoid

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

  1. Do not allow unmonitored outbound TCP traffic to dynamic DNS domains commonly used by underground RAT controllers.
  2. Avoid executing unknown executable files downloaded from hobbyist developer forums.

References & External Analysis

Frequently Asked Questions

What is Serenity RAT?

Serenity RAT is a mid-2000s Remote Access Trojan developed by Killua in Belgium featuring a modular client-server management interface.

What capabilities did Serenity RAT provide?

It provided multi-threaded remote desktop capture, keystroke recording, process injection, registry editing, and shell access.

How did Serenity RAT maintain persistence?

It created autostart registry entries under CurrentVersion\Run and could inject into explorer.exe upon boot.

Which CVE vulnerabilities have been linked to Serenity RAT delivery?

Campaigns distributing retro RAT droppers have leveraged shortcut and document flaws including CVE-2010-2568 and CVE-2012-0158.

How is Serenity RAT eradicated?

Isolate the host, terminate the malicious process, remove registry startup keys, and perform a full malware signature scan.

How do I remove the Serenity_Rat Rat from Windows?

Manual removal of Serenity_Rat is highly discouraged as it may leave persistence mechanisms intact. We recommend disconnecting the device from the internet and utilizing a professional incident response service or enterprise-grade EDR software to conduct a full forensic sweep.

Is Serenity_Rat a virus or a Rat?

Serenity_Rat is classified as a Rat. Unlike traditional viruses that infect files, modern malware like Serenity_Rat typically operates as a standalone payload designed to compromise systems, steal data, or deploy secondary stage implants.

What are the main symptoms of a Serenity_Rat infection?

Symptoms of Serenity_Rat can include unexpected system slowness, unauthorized outbound network traffic to unknown IP addresses, disabled security software, and suspicious background processes running from AppData or Temp directories.

Protect Your Network Against Rats

Want to prevent Serenity_Rat and similar threats from compromising your organization? Read our comprehensive defensive guide: Backdoor & RAT Protection for Businesses.

📣 Threat Intel Correction or Update?

Notice an outdated IOC, unlisted alias, or disputed attribution? Threat researchers are invited to propose an update on GitHub or contact the SystemHelpDesk research desk. All community revisions are credited in our public CHANGELOG.

Need help with an active incident? Published by the SystemHelpdesk Threat Intelligence Team.

Machine-readable

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