BlackFile Extortion Group: Defending Retail and Hospitality Against Vishing-Led Data Theft

---
title: BlackFile Indicator - Suspicious Remote Admin Tool Installation
id: 8f3c2d12-5a4b-4e1a-9c8d-1e2f3a4b5c6d
status: experimental
description: Detects the installation of common remote administration tools often used in vishing schemes to gain access. References specific BlackFile TTPs involving helpdesk fraud.
references:
  - https://attack.mitre.org/techniques/T1219/
author: Security Arsenal
date: 2026/04/06
tags:
  - attack.command_and_control
  - attack.t1219
logsource:
  category: process_creation
  product: windows
detection:
  selection:
    Image|endswith:
      - '\AnyDesk.exe'
      - '\sc.exe'
      - '\ConnectwiseControl.Client.exe'
      - '\Splashtop.exe'
      - '\AteraAgent.exe'
    CommandLine|contains:
      - 'install'
      - 'create'
  filter:
    ParentImage|contains:
      - '\Program Files\'
      - '\Windows\System32\'
  condition: selection and not filter
falsepositives:
  - Legitimate IT administration (should be restricted to specific admin accounts)
level: high
---
title: BlackFile Indicator - PowerShell Data Staging for Exfiltration
id: 9d4e3f23-6b5c-5f2b-0d9e-2f3a4b5c6d7e
status: experimental
description: Detects PowerShell commands used to compress multiple files, a common step before data exfiltration in extortion attacks.
references:
  - https://attack.mitre.org/techniques/T1560/
author: Security Arsenal
date: 2026/04/06
tags:
  - attack.collection
  - attack.t1560.001
logsource:
  category: process_creation
  product: windows
detection:
  selection:
    Image|endswith:
      - '\powershell.exe'
      - '\pwsh.exe'
    CommandLine|contains:
      - 'Compress-Archive'
      - '-Path'
      - '-DestinationPath'
  context:
    CommandLine|contains:
      - '.zip'
      - 'C:\Temp\'
      - 'C:\Users\Public\'
  condition: selection and context
falsepositives:
  - System backup scripts
level: medium
---
title: BlackFile Indicator - Local User Creation via Command Line
id: 0a1b2c3d-4e5f-6a7b-8c9d-0e1f2a3b4c5d
status: experimental
description: Detects creation of new local users via net.exe or PowerShell, often used by vishers to maintain persistence after tricking help desk staff.
references:
  - https://attack.mitre.org/techniques/T1136/
author: Security Arsenal
date: 2026/04/06
tags:
  - attack.persistence
  - attack.t1136.001
logsource:
  category: process_creation
  product: windows
detection:
  selection:
    Image|endswith:
      - '\net.exe'
      - '\net1.exe'
    CommandLine|contains:
      - ' user '
      - ' /add'
  condition: selection
falsepositives:
  - Authorized administrative user creation
level: high

// Hunt for BlackFile activity: Unusual remote access tools and user creation
// Covers process execution and sign-in anomalies
let RemoteAdminTools = dynamic(["AnyDesk.exe", "sc.exe", "ConnectwiseControl.Client.exe", "Splashtop.exe", "AteraAgent.exe"]);
let SuspiciousCommands = dynamic(["Compress-Archive", "user ", "/add"]);
// Check for process creation of remote tools or suspicious commands
DeviceProcessEvents
| where Timestamp > ago(30d)
| where FileName in~ RemoteAdminTools 
   or (ProcessCommandLine has_any (SuspiciousCommands) and 
       (FolderPath endswith "\\powershell.exe" or FolderPath endswith "\\pwsh.exe" or FolderPath endswith "\\net.exe"))
| project Timestamp, DeviceName, InitiatingProcessAccountName, FileName, ProcessCommandLine, FolderPath
| extend HuntType = case(
    FileName in~ RemoteAdminTools, "RemoteAdminTool",
    ProcessCommandLine has "Compress-Archive", "DataStaging",
    ProcessCommandLine has "user", "UserCreation",
    "Other"
)
| join kind=leftouter (
    IdentityLogEvents
    | where Timestamp > ago(30d)
    | where ActionType == "UserLoggedIn" 
    | project Timestamp, AccountName, Latitude, Longitude
) on $left.InitiatingProcessAccountName == $right.AccountName, $left.Timestamp == $right.Timestamp
| order by Timestamp desc

// Hunt for BlackFile persistence mechanisms and data staging
// 1. Check for common remote admin binaries
// 2. Look for recently created zip files in user directories
SELECT 
  OSPath, 
  Size, 
  Mtime, 
  Mode.String AS Mode
FROM glob(globs="/*")
WHERE Name =~ "AnyDesk" 
   OR Name =~ "ScreenConnect" 
   OR Name =~ "Splashtop"

UNION ALL

SELECT 
  OSPath, 
  Size, 
  Mtime, 
  Mode.String AS Mode
FROM glob(globs="/Users/*/AppData/Local/Temp/*.zip")
WHERE Mtime > now() - 7d

# Remediation Script: Audit for BlackFile TTPs
# 1. Checks for presence of common remote management tools
# 2. Audits recent local user creations

Write-Host "[+] Starting BlackFile TTP Audit..." -ForegroundColor Cyan

# Define suspicious remote admin tools
$suspiciousSoftware = @(
    "AnyDesk",
    "Splashtop",
    "ConnectWise",
    "Atera",
    "ScreenConnect"
)

# Check for installed software matching suspicious names
Write-Host "[*] Checking for Remote Administration Tools..." -ForegroundColor Yellow
$foundTools = Get-ItemProperty "HKLM:\\Software\\Microsoft\\Windows\\CurrentVersion\\Uninstall\\*",
                          "HKLM:\\Software\\Wow6432Node\\Microsoft\\Windows\\CurrentVersion\\Uninstall\\*" |
    Where-Object { $suspiciousSoftware -match $_.DisplayName } |
    Select-Object DisplayName, DisplayVersion, InstallDate

if ($foundTools) {
    Write-Host "[!] WARNING: Found potentially unauthorized remote admin software:" -ForegroundColor Red
    $foundTools | Format-Table -AutoSize
} else {
    Write-Host "[+] No common remote admin tools found in registry." -ForegroundColor Green
}

# Check for recent local user creation (last 7 days)
Write-Host "[*] Auditing recent local user accounts..." -ForegroundColor Yellow
$cutoffDate = (Get-Date).AddDays(-7)
$localUsers = Get-LocalUser | Where-Object { $_.LastLogon -gt $cutoffDate -or $_.PasswordLastSet -gt $cutoffDate }

if ($localUsers) {
    Write-Host "[!] WARNING: Local users created or modified in the last 7 days:" -ForegroundColor Red
    $localUsers | Select-Object Name, Enabled, LastLogon, PasswordLastSet | Format-Table -AutoSize
} else {
    Write-Host "[+] No new local user activity detected." -ForegroundColor Green
}

Write-Host "[+] Audit Complete." -ForegroundColor Cyan