Dreambot
Table of Contents
Overview
DreamBot (also recognized as a prominent branch of the Ursnif/ISFB banking trojan family, tracked under designations including Trojan:Win32/DreamBot, Trojan:Win32/Ursnif.DreamBot, and Win32/DreamBot) is a sophisticated modular banking trojan and info-stealer active since 2014. Distributed via malspam campaigns containing macro-enabled Microsoft Word/Excel attachments, DreamBot deploys complex anti-analysis techniques including Tor-based C2 communication, Domain Generation Algorithms (DGA), and API hashing. DreamBot injects code into explorer.exe and web browsers, conducting Man-in-the-Browser (MitB) attacks, capturing keystrokes, stealing digital certificates, and intercepting online banking credentials and cryptocurrency wallet data.
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: Trojan:Win32/Ursnif · Trojan:Win32/Isfb
Known Derivatives & Downstream Variants: Trojan:Win32/Dreambot.A · Trojan:Win32/Dreambot.B
MITRE ATT&CK Techniques
This family has been observed using the following ATT&CK techniques: T1185 · T1056.001 · T1055.001 · T1568.002 · T1090.003
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.
- T1185: Enforce strong MFA and use browser isolation or hardened browsers for sensitive financial or administrative portals to defeat session hijacking.
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-DIA | DLL Injection Analysis | Detect | T1055.001 | Monitor remote thread creation (CreateRemoteThread) and unauthorized DLL loading into core Windows processes (svchost.exe, explorer.exe). |
D3-MFA | Multi-factor Authentication | Harden | T1056.001 | Enforce FIDO2 / WebAuthn physical tokens to render keystroke-intercepted passwords useless. |
D3-OAA | Outbound Network Traffic Filtering | Isolate | T1090.003 | Restrict outbound connections to known external proxy relays and enforce enterprise forward proxy authentication. |
D3-MitBA | Man-in-the-Browser Analysis | Detect | T1185 | Deploy browser extension whitelisting and hardware-backed session binding to prevent rogue DOM and socket injection. |
D3-DNSR | DNS Reputation Analysis | Detect | T1568.002 | Deploy recursive DNS security resolvers with algorithmic domain scoring (entropy and n-gram models) to automatically sinkhole DGA queries. |
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_DREAMBOT_T1_ARTIFACT {
meta:
description = "Tier 1 Primitive Artifact: Raw string matches for Dreambot"
tier = "T1 - Primitive Artifact"
confidence = "Low-Medium (Fast Triage)"
author = "SystemHelpdesk Threat Research Desk"
date = "2026-10-14"
strings:
$s1 = "dreambot" ascii wide nocase
$s2 = "trojan:win32/dreambot" ascii wide nocase
$s3 = "trojan:win32/ursnif.dreambot" ascii wide nocase
$s4 = "win32/dreambot" ascii wide nocase
$s5 = "dreambot banking trojan" ascii wide nocase
$s6 = "ursnif-dreambot" 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 - Dreambot (Banking Trojan) Execution & Triage
id: 0406ce93-c065-5bb7-b29e-5bf8df9f4169
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
with the Dreambot malware family. Detects recon staging, certutil file payload staging,
and web-inject process proxying characteristic of banking trojan initial loaders.
references:
- https://malware-families-catalog.systemhelpdesk.com/families/dreambot
- https://malware-families-catalog.systemhelpdesk.com/defensive/banking-trojan-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.banking-trojan
- author.ricky-jordan
- source.systemhelpdesk-mfc
- attack.t1185
- attack.t1056_001
- attack.t1055_001
- attack.t1568_002
- attack.t1090_003
logsource:
category: process_creation
product: windows
detection:
selection_process:
Image|endswith:
- \svchost.exe
- \explorer.exe
- \msiexec.exe
- \certutil.exe
CommandLine|contains:
- -urlcache
- -split -f
- ipconfig /all
- route print
- netstat -ano
condition: selection_process
falsepositives:
- Legitimate enterprise administrative scripts during approved change windows
- Authorized IT software deployment utilities and backup management agents
level: highTier 3 Attribution Fingerprint Rule (High Fidelity)
Deep signature matching distinctive operational fingerprints and payload characteristics.
rule MALWARE_WIN_DREAMBOT_T3_ATTRIBUTION {
meta:
description = "Tier 3 Attribution Fingerprint: Heuristic detection for Dreambot 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 = "dreambot" 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
Frequently Asked Questions
What is Trojan:Win32/DreamBot?
DreamBot is an Ursnif/ISFB-derived modular banking trojan that steals credentials via Tor-based C2 and Man-in-the-Browser attacks.
How does DreamBot conceal its command-and-control communication?
It communicates through Tor onion routing nodes and backup Domain Generation Algorithms (DGA) to evade network blocking.
What browser mechanisms does DreamBot exploit to steal data?
It injects into web browsers (Chrome, Firefox, Edge) to intercept form data, session cookies, and banking credentials.
How is DreamBot delivered to victims?
It is delivered through malicious spam campaigns delivering macro-laced Office documents and weaponized zip archives.
What defensive measures protect against DreamBot infections?
Block inbound emails containing macro-enabled documents, monitor for unauthorized Tor traffic, and enforce hardware MFA.
How do I remove Dreambot from Windows?
Manual removal of Dreambot 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.
What are the main symptoms of a Dreambot infection?
Symptoms of Dreambot 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 Banking_Trojans
Want to prevent Dreambot 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/dreambot.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.