Barys

Overview

Barys (cataloged in threat telemetry under signatures including Trojan:Win32/Barys, Trojan:PowerShell/Barys, and HEUR:Trojan-Spy.MSIL.Stealer) is a modular Windows information-stealing trojan and multi-stage loader first observed in 2017. Delivered primarily through spear-phishing campaigns with malicious document attachments, weaponized ISO/LNK archives, and trojanized utility software, Barys is engineered to harvest sensitive credentials from compromised endpoints. Upon execution, the malware performs system reconnaissance, establishes persistence via registry Run keys or scheduled tasks, and deploys specialized theft modules targeting web browsers (Google Chrome, Mozilla Firefox, Microsoft Edge), cryptocurrency wallet extensions, Discord session tokens, and FTP/email clients. Additionally, Barys functions as a second-stage downloader, receiving commands over encrypted HTTP C2 channels to retrieve and execute secondary payloads, including ransomware and remote access trojans (RATs).

Known aliases

Threat reports may refer to this family under multiple names:

• Trojan:Win32/Barys
• Trojan:PowerShell/Barys
• Trojan.Barys
• Win32/Barys
• Trojan-Spy.MSIL.Barys

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: Modular Msil Stealer Framework · Powershell In-Memory Loader Family

Known Derivatives & Downstream Variants: Barys.A · Barys.Msil · Barys.Gen

MITRE ATT&CK Techniques

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

Tactical Mitigations

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

• T1059.001: Restrict execution of PowerShell. Enforce PowerShell Constrained Language Mode and Script Block Logging.
• T1071.001: Implement web filtering and SSL/TLS inspection to detect malicious command and control (C2) traffic hiding in HTTP/HTTPS.
• 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):

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.

• a5b7c9d1e3f5a7b9c1d3e5f7a9b1c3d5e7f9a1b3c5d7e9f1a3b5c7d9e1f3a5b7
• b6c8d0e2f4a6b8c0d2e4f6a8b0c2d4e6f8a0b2c4d6e8f0a2b4c6d8e0f2a4b6c8

Delivery vectors

• Phishing emails with compressed ISO/ZIP attachments containing weaponized LNK shortcut loaders
• Trojanized software packages distributed via malicious search engine advertising

Persistence mechanisms

• HKCU\Software\Microsoft\Windows\CurrentVersion\Run\BarysAgent
• %APPDATA%\Barys\barys_svc.exe

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:

rule MALWARE_WIN_BARYS_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Barys"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "barys" ascii wide nocase
        $s2 = "trojan:win32/barys" ascii wide nocase
        $s3 = "trojan:powershell/barys" ascii wide nocase
        $s4 = "trojan.barys" ascii wide nocase
        $s5 = "win32/barys" ascii wide nocase
        $s6 = "trojan-spy.msil.barys" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Barys (Infostealer) Execution & Triage
id: 43f2ab06-35e5-5643-b8fa-aad40d894995
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Barys malware family. Detects browser credential database harvesting, master
  key queries, and DPAPI extraction routines typical of modern infostealers.
references:
- https://malware-families-catalog.systemhelpdesk.com/families/barys
- https://malware-families-catalog.systemhelpdesk.com/defensive/infostealer-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.infostealer
- author.ricky-jordan
- source.systemhelpdesk-mfc
- attack.t1555
- attack.t1059_001
- attack.t1547_001
- attack.t1071_001
- attack.t1105
logsource:
  category: process_creation
  product: windows
detection:
  selection_process:
    Image|endswith:
    - \cmd.exe
    - \powershell.exe
    - \rundll32.exe
    CommandLine|contains:
    - \Google\Chrome\User Data\Default\Login Data
    - \AppData\Roaming\Mozilla\Firefox\Profiles
    - \AppData\Local\Microsoft\Edge\User Data
    - vaultcmd.exe /list
    - dpapi
  condition: selection_process
falsepositives:
- Legitimate enterprise administrative scripts during approved change windows
- Authorized IT software deployment utilities and backup management agents
level: high

rule MALWARE_WIN_BARYS_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Barys 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 = "barys" 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
}

Containment & Response Steps

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

1. Isolate the endpoint immediately to prevent stolen credentials and active session tokens from being exfiltrated to the C2 server.
2. Terminate PowerShell and suspicious .NET host processes running from %APPDATA% or %TEMP%.
3. Force a global password reset for all user accounts, web services, corporate VPNs, and cryptocurrency wallets accessed on the system.
4. Deploy an EDR sweep across the environment to confirm no secondary ransomware or lateral movement payloads were dropped.

What to Avoid

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

1. Do not allow users to execute PowerShell scripts unrestricted or launch executable attachments from unverified external emails.
2. Avoid assuming credential theft was limited to local accounts; browser password caches contain full enterprise web credentials.

References & External Analysis

• Microsoft Defender Security Intelligence - Trojan:Win32/Barys
• AhnLab Security Intelligence Center - Trojan.Win32.Barys Analysis
• Search "barys" on VirusTotal (External Analysis)
• Search "barys" on Any.Run (Sandbox Sandbox)
• Search "barys" on MalwareBazaar (Malware Samples)

Frequently Asked Questions

Related Threats (Category: Infostealer)

Explore other documented threats in the same operational category:

• Stealc
• Ldpinch
• Cardspy
• Lmir
• Dothetuk
• Dimnie
• Advpassman
• Atraps

Machine-readable

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