Zurgop
Table of Contents
Overview
Zurgop (tracked across antimalware research repositories under detections including Trojan:Win32/Zurgop, TrojanDownloader:Win32/Zurgop, and Trojan.Zurgop) is a resilient multi-stage Windows trojan loader and initial access agent active since 2016. Infiltrating target environments through malicious email attachments, cracked software repositories, and exploit kits, Zurgop is engineered to provide persistent foothold access and facilitate subsequent payload deployment. Once active, Zurgop performs extensive system reconnaissance, enumerating host OS build details, installed antivirus software, and user privilege levels. It establishes persistence via registry autostart configurations and establishes encrypted outbound communication channels with remote C2 infrastructure. Threat actors leverage Zurgop to deploy diverse secondary malware families, notably ransomware, information stealers, and banking trojans, while leveraging process injection techniques into svchost.exe to evade host-based anomaly detection.
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:
Known Derivatives & Downstream Variants: Trojan:Win32/Zurgop.A · Trojan:Win32/Zurgop.B
MITRE ATT&CK Techniques
This family has been observed using the following ATT&CK techniques: T1059.003 · T1055 · T1105 · T1082 · T1547.001
Tactical Mitigations
Based on the techniques used by this family, consider the following defensive strategies:
- T1059.003: Restrict execution of Windows Command Shell (cmd.exe) and block unauthorized batch scripts.
- T1105: Implement network intrusion detection systems (NIDS) and host-based firewalls to block unauthorized inbound or outbound file transfers.
MITRE D3FEND™ Defensive Countermeasures
Defensive techniques mapped to counter the offensive tradecraft observed in this family (via the MITRE D3FEND matrix):
| D3FEND ID | Countermeasure Name | Tactic | Countered ATT&CK | Defensive Guidance |
|---|---|---|---|---|
D3-PIAD | Process Injection Analysis & Detection | Detect | T1055 | Monitor cross-process thread creation (CreateRemoteThread) and asynchronous procedure calls (QueueUserAPC). |
D3-PBA | Process Spawn Analysis | Detect | T1059.003 | Inspect command-line arguments and anomalous parent-child relationships spawning from cmd.exe. |
D3-SDA | System Discovery Analysis | Detect | T1082 | Alert on rapid enumerations of systeminfo, hostname, and registry hardware trees in short intervals. |
D3-NTI | Network Traffic Inspection | Detect | T1105 | Inspect deep packet payloads for anomalous staging binaries and unauthorized egress protocols. |
D3-RPM | Registry Persistence Monitoring | Detect | T1547.001 | Audit and restrict write privileges to user and machine-level Registry Run/RunOnce keys using Endpoint Privilege Management. |
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_ZURGOP_T1_ARTIFACT {
meta:
description = "Tier 1 Primitive Artifact: Raw string matches for Zurgop"
tier = "T1 - Primitive Artifact"
confidence = "Low-Medium (Fast Triage)"
author = "SystemHelpdesk Threat Research Desk"
date = "2026-10-14"
strings:
$s1 = "zurgop" ascii wide nocase
$s2 = "trojan:win32/zurgop" ascii wide nocase
$s3 = "trojandownloader:win32/zurgop" ascii wide nocase
$s4 = "trojan.zurgop" ascii wide nocase
$s5 = "win32/zurgop" ascii wide nocase
$s6 = "trojan:win32/zurgop.a" 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 - Zurgop (Trojan) Execution & Triage
id: 3bec8281-6eef-54a8-ad35-1b6a40702753
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
with the Zurgop 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/zurgop
- 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_003
- attack.t1055
- attack.t1105
- attack.t1082
- attack.t1547_001
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: mediumTier 3 Attribution Fingerprint Rule (High Fidelity)
Deep signature matching distinctive operational fingerprints and payload characteristics.
rule MALWARE_WIN_ZURGOP_T3_ATTRIBUTION {
meta:
description = "Tier 3 Attribution Fingerprint: Heuristic detection for Zurgop 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 = "zurgop" 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
- Microsoft Defender Threat Encyclopedia - Trojan:Win32/Zurgop
- Trend Micro Threat Encyclopedia - Trojan.Win32.Zurgop
- Search "zurgop" on VirusTotal (External Analysis)
- Search "zurgop" on Any.Run (Sandbox Sandbox)
- Search "zurgop" on MalwareBazaar (Malware Samples)
Frequently Asked Questions
What is Trojan:Win32/Zurgop?
Zurgop is a multi-stage Windows trojan loader used by cybercriminals to maintain access and deploy secondary payloads like ransomware.
How does Zurgop infiltrate computer systems?
It infects computers via phishing emails with malicious attachments, weaponized downloads from torrent sites, and exploit kits.
What secondary payloads are delivered by Zurgop?
Zurgop commonly downloads and drops crypto-ransomware, credential stealers, keyloggers, and banking trojans.
How does Zurgop evade security detection?
It injects payload shellcode into svchost.exe, uses PEB hashing for dynamic API resolution, and employs anti-sandbox delays.
What remediation steps should be taken if Zurgop is detected?
Isolate the infected device, perform full antimalware scanning, terminate injected processes, and audit for secondary dropped payloads.
How do I remove the Zurgop Trojan from Windows?
Manual removal of Zurgop 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 Zurgop a virus or a Trojan?
Zurgop is classified as a Trojan. Unlike traditional viruses that infect files, modern malware like Zurgop typically operates as a standalone payload designed to compromise systems, steal data, or deploy secondary stage implants.
What are the main symptoms of a Zurgop infection?
Symptoms of Zurgop 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 Trojans
Want to prevent Zurgop and similar threats from compromising your organization? Read our comprehensive defensive guide: Banking Trojan 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.
Machine-readable
Get this profile as JSON: https://malware-families-catalog.systemhelpdesk.com/api/zurgop.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.