DecliningWindowsCredential theft
Malware Intelligence

Phantom Stealer

Phantom Stealer is a fork of Stealerium and overlaps heavily with its source code.

Activity map

Proofpoint

Activity mapAttachmentExtractionExecutionPackagingExfiltrationPhishing emailInvoice, shipmentZIPArchiveEXE.NET payloadPhantom StealerInfostealerData collection9 targetsLog archiveC2 server
Executable payloadFile
Malicious payloadPhantom Stealer · Infostealer

Phantom Stealer is a fork of Stealerium and overlaps heavily with its source code.

Environment information

  • Operating system
  • Hardware
  • IP and location
  • Installed software

Credentials and application data

  • Saved passwords
  • Session cookies
  • Autofill
  • Saved cards
  • Steam
  • Telegram
  • Discord
  • Battle.net
  • Mozilla Thunderbird
Dark Radar infection records
127
Latest infection record
12 June 2026
Malware type
Infostealer
First seen
2025
01

Overview

Ranks 50 of 52 families in Dark Radar data, with 127 infection records.

02

Origin and evolution

  1. 2025Began to be tracked as a Stealerium derivative.Proofpoint
03

Technical profile

Malware typeInfostealer
Target operating systemWindows
Primary purposeData theft
Threat categoryCredential theft
Programming languageC#
Distribution modelSale
First seen2025
Infected systemsWindows 10 70.9%, Windows 11 27.6%
Public source confidenceMedium
04

Targeted applications

9 applications5 categories
05

Data collection

Credentials

  • Browser passwords78.7%Version-dependent
  • Session cookies52%Version-dependent
  • Refreshing expired sessions—
  • Autofill37.8%Dark Radar observation
  • macOS Keychain—
  • 2FA and password managers—

Financial

  • Saved cards7.1%Dark Radar observation
  • Desktop crypto wallets26%Version-dependent
  • Wallet extensions—
  • Clipboard address replacement—

Applications

  • Email clients3.1%Dark Radar observation
  • FTP clients—
  • VPN clients—
  • Messaging applications29.9%Version-dependent
  • Gaming platforms68.5%Dark Radar observation

System

  • File collection—
  • Screenshot—
  • System inventory99.2%Dark Radar observation
06

File system

User profile (%USERPROFILE%)
File details are in Dark Radar IntelligenceOpen in Intelligence
07

How it works

  1. 1Discovery

    Dark Radar observation

    Infected systems: Windows 10 70.9%, Windows 11 27.6%.

    Breaking point: Bulk system and security software queries from a short-lived process trigger an EDR alert.

  2. 2Data collection

    Dark Radar observation

    Data found in the latest 127 logs: password file 78.7%, cookies 52%, autofill 37.8%, cards 7.1%, wallets 26%.

    Breaking point: A process other than the browser reading browser profile files is blocked or triggers an alert.

08

IOCs and detection

This section is in Dark Radar IntelligenceOpen in Intelligence
09

Risk and impact

  • Stolen session cookies are enough to take over cloud, email and SaaS sessions without a password or multi-factor authentication prompt.
  • Corporate passwords saved on personal devices also leak through infections outside the corporate network; these logs are sold to initial access brokers.
  • Log archives are reshared for years; as long as the password is not changed, the same credential can be used again and again.
  • Compromised email, messaging and social media accounts become the next link in phishing and malware distribution.
10

Defense

  • When an infection is detected, revoke not only the password but all related sessions and access tokens.
  • Turn off password saving in the browser through corporate policy; use a corporate password manager.
  • Move to phishing-resistant multi-factor authentication (FIDO2/passkey); bind sessions to the device.
  • Block setup files downloaded from unlicensed software, game cheats and sponsored search results.
  • Monitor flows where the user runs a command by pasting it into the Run dialog or terminal (ClickFix) with endpoint rules.
  • Continuously monitor your corporate domains and employee email addresses in stealer logs with Dark Radar.
11

Learning center

How does this malware spread?
  • Infostealer families mostly spread through unlicensed software, fake updates, sponsored search ads and phishing emails.
How can its presence on a system be detected?
  • Sign-ins to accounts from an unrecognized country or device.
  • A new infostealer log in Dark Radar for your corporate domain or an employee email address.
Which Windows artifacts should be examined?
  • Prefetch (C:\Windows\Prefetch) — shows that a short-lived payload ran.
  • Amcache.hve and ShimCache — path and hash of the executed file.
  • Downloads folder and Zone.Identifier stream — the address the file was downloaded from.
  • Browser history — the fake download page or fake CAPTCHA address.
  • RunMRU registry key — commands pasted into the Run dialog.
  • Randomly named folders and DLLs under %TEMP% and %LOCALAPPDATA%.
Which log records matter?
  • Sysmon Event 1 / Security 4688Process creation: unsigned processes starting from Temp and Downloads folders, mshta, powershell -enc chains.
  • Sysmon Olay 11 / 23File creation and deletion: self-deleting payloads, DLLs dropped under Temp.
  • Sysmon Olay 3 / 22Network connection and DNS query: to newly registered domains, C2 resolution via Telegram, Steam or Pastebin.
  • Object access auditing (4663)A process other than the browser reading Login Data, Cookies and Local State files.
  • PowerShell 4104Script block logging: obfuscated downloader commands.
  • Identity provider sign-in logsSessions after the infection from a different country and device, without a multi-factor authentication prompt.
How should a SOC analyst respond?
  1. Isolate the device from the network; do not reinstall it before taking memory and disk images.
  2. Determine the infection date; list all accounts that were signed in on the device after that date.
  3. Change the passwords of these accounts, revoke their sessions and access tokens, and re-enroll multi-factor authentication devices.
  4. Search identity provider and SaaS logs for new country, device and token usage after the infection.
  5. If a recovery phrase or wallet file was exposed, move the assets to a new wallet.
  6. Find the initial access path (email, ad, unlicensed software, fake CAPTCHA) and check other users who used the same path.
  7. Reinstall the device from a clean image.
12

Sources

Related families

StealeriumCompare
From the Essential plan

Infostealer Detection

See your firm's attack surface on one screen: how many findings, at which severity, on which domain.

View productCompare plans