Ursnif
Overview
Ursnif is a banking trojan and a variant of the Gozi malware. According to MITRE ATT&CK, it has been spread through automated exploit kits, spearphishing attachments, and malicious links. While it is associated primarily with data theft, some variants add components such as backdoors, spyware, and file injectors, giving it a wide range of behaviors. Its long lineage and several code leaks have produced many related variants tracked under names like Gozi-ISFB and Dreambot.
Known aliases
Threat reports may refer to this family under multiple names:
MITRE ATT&CK Techniques
This family has been observed using the following ATT&CK techniques: T1566.001 T1185 T1071.001 T1055
Tactical Mitigations
Based on the techniques used by this family, consider the following defensive strategies:
- T1071.001: Implement web filtering and SSL/TLS inspection to detect malicious command and control (C2) traffic hiding in HTTP/HTTPS.
- T1185: Enforce strong MFA and use browser isolation or hardened browsers for sensitive financial or administrative portals to defeat session hijacking.
- T1566.001: Scan email attachments for malicious macros, scripts, or suspicious archive files.
Generated Detections (Boilerplate)
These YARA and Sigma rules are auto-generated based on the family name and aliases. They must be heavily tuned before deployment in a production environment.
YARA Rule
rule MALWARE_WIN_URSNIF {
meta:
description = "Detects Ursnif (banking_trojan)"
author = "SystemHelpdesk Boilerplate Generator"
date = "2026-07-06"
strings:
$s1 = "ursnif" ascii wide nocase
$s2 = "ursnif" ascii wide nocase
$s3 = "gozi-isfb" ascii wide nocase
$s4 = "dreambot" ascii wide nocase
$s5 = "isfb" ascii wide nocase
condition:
uint16(0) == 0x5a4d and any of them
}Sigma Rule
title: Suspicious Ursnif Activity
id: 1bba09eb98151e0bd46d8c9227e8282e
status: experimental
description: Detects generic indicators of the ursnif malware family.
logsource:
category: process_creation
product: windows
detection:
selection:
Image|endswith:
- '\cmd.exe'
- '\powershell.exe'
CommandLine|contains:
- "*ursnif*"
- "*ursnif*"
- "*gozi-isfb*"
- "*dreambot*"
- "*isfb*"
condition: selection
level: mediumReferences & External Analysis
- MITRE ATT&CK: Ursnif (S0386)
- Search "ursnif" on VirusTotal (External Analysis)
Frequently Asked Questions
What is Ursnif?
A banking trojan derived from the Gozi malware family, focused mainly on stealing banking credentials and other sensitive data.
What other names does Ursnif go by?
It is tracked under names including Gozi, Gozi-ISFB, ISFB, and Dreambot, reflecting its shared code lineage and multiple variants.
How does Ursnif spread?
MITRE documents distribution through automated exploit kits, spearphishing email attachments, and malicious links.
What does Ursnif do once it infects a machine?
It is associated primarily with data theft, but certain variants add backdoors, spyware, and file-injection components for broader control.
Why are there so many Ursnif variants?
The underlying Gozi/ISFB source code has leaked more than once, letting different actors build their own versions.
How can I reduce exposure to banking trojans like Ursnif?
Keep your browser and OS patched (which closes exploit-kit holes), be wary of unexpected email attachments and links, and use multi-factor authentication on financial accounts so stolen passwords alone are not enough.
Where is the authoritative source for Ursnif?
MITRE ATT&CK's Ursnif entry (S0386), linked on this page, documents its observed techniques and references vendor research.
How do I remove the Ursnif Banking_Trojan from Windows?
Manual removal of Ursnif 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 Ursnif a virus or a Banking_Trojan?
Ursnif is classified as a Banking_Trojan. Unlike traditional viruses that infect files, modern malware like Ursnif typically operates as a standalone payload designed to compromise systems, steal data, or deploy secondary stage implants.
What are the main symptoms of a Ursnif infection?
Symptoms of Ursnif 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.
Related Families (Category: banking_trojan)
Explore other malware families in the same category:
Protect Your Network Against Banking_Trojans
Want to prevent Ursnif and similar threats from compromising your organization? Read our comprehensive defensive guide: Banking Trojan Protection.
Machine-readable
Get this profile as JSON: https://jordan123234-malware-families-explorer.static.hf.space/api/ursnif.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.