Dostre
Table of Contents
Overview
Dostre (identified across security telemetry and antivirus engines as Trojan:Win32/Dostre, Ransom:Win32/Dostre, and Trojan.Dostre) is a multi-stage Windows trojan and initial compromise agent active since 2016. Frequently distributed through spam email attachments, malicious software keygens, and compromised torrent distributions, Dostre establishes an initial foothold by deploying heavily obfuscated stubs into hidden user directories. Dostre conducts immediate host discovery—querying local hardware specifications, active antivirus processes, and network interfaces—before communicating with remote C2 servers via encrypted HTTP beacons. Depending on instructions returned from the C2 infrastructure, Dostre can act as an extortion screen locker, deploy secondary ransomware modules, or inject backdoor routines into native Windows processes like svchost.exe to establish long-term persistence.
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/Dostre.A · Ransom:Win32/Dostre.B
MITRE ATT&CK Techniques
This family has been observed using the following ATT&CK techniques: T1055 · T1071.001 · T1486 · T1547.001 · T1082
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.
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-WAF | Web Content Filtering & Inspection | Filter | T1071.001 | Block newly registered domains (NRDs) and inspect HTTP Host and URI headers for known C2 profiles. |
D3-SDA | System Discovery Analysis | Detect | T1082 | Alert on rapid enumerations of systeminfo, hostname, and registry hardware trees in short intervals. |
D3-FAED | File Alteration Early Detection | Detect | T1486 | Deploy canary files and monitor mass rename/encryption I/O spikes to terminate ransomware threads immediately. |
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_DOSTRE_T1_ARTIFACT {
meta:
description = "Tier 1 Primitive Artifact: Raw string matches for Dostre"
tier = "T1 - Primitive Artifact"
confidence = "Low-Medium (Fast Triage)"
author = "SystemHelpdesk Threat Research Desk"
date = "2026-10-14"
strings:
$s1 = "dostre" ascii wide nocase
$s2 = "trojan:win32/dostre" ascii wide nocase
$s3 = "ransom:win32/dostre" ascii wide nocase
$s4 = "trojan.dostre" ascii wide nocase
$s5 = "win32/dostre" ascii wide nocase
$s6 = "trojan:win32/dostre.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 - Dostre (Trojan) Execution & Triage
id: 21aeab4a-7860-5ab5-aaed-557fc7792ed7
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
with the Dostre 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/dostre
- 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.t1055
- attack.t1071_001
- attack.t1486
- attack.t1547_001
- attack.t1082
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_DOSTRE_T3_ATTRIBUTION {
meta:
description = "Tier 3 Attribution Fingerprint: Heuristic detection for Dostre 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 = "dostre" 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/Dostre
- Trend Micro Threat Encyclopedia - Trojan.Win32.Dostre
- Search "dostre" on VirusTotal (External Analysis)
- Search "dostre" on Any.Run (Sandbox Sandbox)
- Search "dostre" on MalwareBazaar (Malware Samples)
Frequently Asked Questions
What is Trojan:Win32/Dostre?
Dostre is a multi-stage Windows trojan and initial access threat that delivers secondary malware payloads and extortion routines.
How does Dostre maintain persistence on infected systems?
It modifies Windows CurrentVersion\Run registry keys and registers background service tasks to re-launch upon system boot.
What evasive tactics are implemented by Dostre?
Dostre inspects the Process Environment Block for debuggers, terminates security processes, and injects code into svchost.exe.
How does Dostre communicate with its command and control servers?
It issues encrypted HTTP POST requests carrying host reconnaissance profiles and downloads secondary binaries disguised as temporary data files.
What defensive measures effectively mitigate Dostre?
Enforce behavioral monitoring on svchost.exe process injections, restrict executable launches from %AppData%, and maintain current antivirus definitions.
How do I remove Dostre from Windows?
Manual removal of Dostre 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 Dostre infection?
Symptoms of Dostre 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 Dostre 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/dostre.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.