Active threat familyWindowsCredential theft
Malware Intelligence

Vidar

Vidar is an infostealer derived from the Arkei code base. Alongside browser data and crypto wallets, it was one of the first families to target two-factor authentication software and Tor Browser.

Activity map

Activity mapAttachmentLaunchesPackagingExfiltrationUser typesDownloadsDownloadDownloadExecutionC2 addressAddressPhishing emailISODisk imageCHMHelp fileEXEHidden payloadhh.exeHelp viewerVidarInfostealerData collection27 targetsLog archiveC2 serverTikTok videoFree softwarePowerShellManually typed commandDownload from aremote serverScriptFake download siteFake Windows 11 download2cLoaderLoader serviceEXEPayloadIntermediateresolverSteam, Telegram profile
Executable payloadFile
Malicious payloadVidar · Infostealer

Vidar is an infostealer derived from the Arkei code base. Alongside browser data and crypto wallets, it was one of the first families to target two-factor authentication software and Tor Browser.

Appears in flows

Environment information

  • Operating system
  • Hardware
  • IP and location
  • Installed software
  • Running processes
  • Screenshot
  • Desktop files

Credentials and application data

  • Saved passwords
  • Session cookies
  • Autofill
  • Saved cards
  • 2FA seeds
  • Discord
  • Telegram
  • Steam
  • MetaMask
  • Authenticator
  • Phantom
  • Coinbase Wallet
  • Trust Wallet
  • Binance Wallet
Dark Radar infection records
5,662,081
Latest infection record
29 October 2026
Malware type
Infostealer
First seen
2018
01

Overview

Active for more than seven years; continuously distributed through loader services.

Ranks 3 of 52 families in Dark Radar data, with 5,662,081 infection records.

02

Origin and evolution

  1. 2018Emerged as a derivative of Arkei.Malpedia (Fraunhofer FKIE)
  2. 2022Arkei-derived families (Vidar, Mars, then StealC) were tracked in the same lineage.SANS ISC
  3. 2023Distributed through backdoored Windows 11 downloads.Zscaler
  4. 2025Virtual machine-based and custom stream-cipher string obfuscation was added.Zscaler
  5. 2026Distributed together with Remus via 2cLoader.Zscaler
03

Technical profile

Malware typeInfostealer
Target operating systemWindows
Primary purposeData theft
Threat categoryCredential theft
Programming languageC++
Distribution modelSale and subscription (MaaS)
First seen2018
Infected systemsWindows 10 50.5%, Windows 11 26.5%
Public source confidenceHigh
04

Targeted applications

27 applications8 categories
05

Data collection

Credentials

  • Browser passwords92%Verified
  • Session cookies95%Verified
  • Refreshing expired sessions—
  • Autofill82.5%Verified
  • macOS Keychain—
  • 2FA and password managersVerified

Financial

  • Saved cards4.5%Verified
  • Desktop crypto walletsVerified
  • Wallet extensionsVerified
  • Clipboard address replacement—

Applications

  • Email clients—
  • FTP clientsVersion-dependent
  • VPN clients—
  • Messaging applications11.5%Version-dependent
  • Gaming platforms6.5%Dark Radar observation

System

  • File collection18%Verified
  • Screenshot7.5%Verified
  • System inventory99%Verified

Behavior

  • Additional payload downloadVerified
  • Persistence—
  • Anti-analysisVerified
06

File system

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

System components

  • Operating system, hardware and installed software
  • Running processes
  • IP address and location
  • Screenshot
08

How it works

  1. 1Infection

    • Loader and pay-per-install (PPI) services.
    • Backdoored software downloads and CHM help files.

    Breaking point: Email attachments, sponsored ad links and unlicensed software downloads are blocked at the email and web gateway.

  2. 2Execution and evasion

    • The configuration is fetched from the C2 server at runtime.
    Dark Radar observation

    The payload ran from the temporary folder (latest 200 logs, 74.7%).

    The payload ran from the LocalAppData folder (latest 200 logs, 9.1%).

    Ran from the install.exe file in the Windows folder (latest 200 logs, 4.5%).

    T1204.002User Execution: Malicious FileT1027Obfuscated Files or InformationT1497Virtualization/Sandbox EvasionT1070.004File Deletion

    Breaking point: Unsigned files running from user folders and injections into .NET tools are stopped by application control and EDR.

  3. 3Discovery

    • A system inventory and a screenshot are taken.
    Dark Radar observation

    Infected systems: Windows 10 50.5%, Windows 11 26.5%, Windows 7 5.5%.

    T1082System Information DiscoveryT1083File and Directory Discovery

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

  4. 4Data collection

    • Legitimate third-party DLLs are downloaded from the C2 to decrypt browser data.
    • Files are collected using file masks defined in the panel.
    Dark Radar observation

    Data found in the latest 200 logs: password file 92%, cookies 95%, autofill 82.5%, cards 4.5%, wallets 1.5%.

    T1555.003Credentials from Web BrowsersT1539Steal Web Session CookieT1005Data from Local SystemT1555.005Password ManagersT1113Screen CaptureT1560Archive Collected Data

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

  5. 5Exfiltration and C2

    • Data is sent as a ZIP archive with HTTP POST.
    T1071.001Web ProtocolsT1041Exfiltration Over C2 ChannelT1102.001Dead Drop ResolverT1105Ingress Tool Transfer

    Breaking point: Traffic to newly registered domains, direct IP addresses and non-standard ports is blocked.

  6. 6Persistence and aftermath

    • An additional payload can be downloaded; it then deletes itself to leave no trace.

    Breaking point: When an infection is confirmed, all sessions and access tokens on the device are revoked.

09

Network communication

This section is in Dark Radar IntelligenceOpen in Intelligence
10

MITRE ATT&CK

Execution
Credential Access
Discovery
Collection
Command and Control
Exfiltration
Defense Evasion
11

IOCs and detection

This section is in Dark Radar IntelligenceOpen in Intelligence
12

Risk and impact

  • When 2FA software data is stolen, the second factor also falls into the attacker's hands.
  • 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.
13

Defense

  • Write detection rules for processes that access social network profiles and then connect to an unknown IP.
  • 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.
14

Learning center

How does this malware spread?
  • Loader and pay-per-install (PPI) services.
  • Backdoored software downloads and CHM help files.
  • The payload ran from the temporary folder (latest 200 logs, 74.7%).
  • The payload ran from the LocalAppData folder (latest 200 logs, 9.1%).
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.
Which MITRE techniques is it associated with?
T1204.002User Execution: Malicious FileT1555.003Credentials from Web BrowsersT1539Steal Web Session CookieT1082System Information DiscoveryT1005Data from Local SystemT1071.001Web ProtocolsT1041Exfiltration Over C2 ChannelT1555.005Password ManagersT1113Screen CaptureT1083File and Directory DiscoveryT1102.001Dead Drop ResolverT1105Ingress Tool TransferT1027Obfuscated Files or InformationT1497Virtualization/Sandbox EvasionT1070.004File DeletionT1560Archive Collected Data
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.
15

Sources

Related families

ArkeiStealCLumma StealerCompare

Related terms

Stealer logsFully UndetectedJoinerCredential leakCommand and control serverInfostealerMalware familyObfuscation
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