Analysis by: Rhena Inocencio


Trojan:Win32/Malagent!gmb (Microsoft), Trojan-Dropper.Win32.Injector.kcnn (Kaspersky)


Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)


  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes


Infection Channel:

Downloaded from the Internet, Dropped by other malware

This backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It executes commands from a remote malicious user, effectively compromising the affected system. It connects to a website to send and receive information.


File Size:


File Type:


Memory Resident:


Initial Samples Received Date:

26 Jun 2014


Drops files, Collects system information

Arrival Details

This backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.


This backdoor drops the following files:

  • %User Temp%\mbCHECK.dll - BKDR_HAVEX.A
  • %System%\svcprocess{version}.dll - BKDR_HAVEX.A
  • %User Temp%\mbCHECK.exe - loader of malicious dll

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.. %System% is the Windows system folder, which is usually C:\Windows\System32.)

Autostart Technique

This backdoor adds the following registry entries to enable its automatic execution at every system startup:

svcprocess = "rundll32 "%System%\svcprocess{version}.dll", RunDllEntry"

svcprocess = "rundll32 "%System%\svcprocess{version}.dll", RunDllEntry"

Other System Modifications

This backdoor modifies the following registry entries:

Internet Explorer\InternetRegistry
fertger = "{random}-{random}"

Backdoor Routine

This backdoor executes the following commands from a remote malicious user:

  • Download and execute arbitrary files/components
  • Upload files
  • Terminate process
  • Get list of drives

It connects to the following websites to send and receive information:

  • {BLOCKED}celebs.{BLOCKED}xycomics.com/wp05/wp-admin/includes/tmp/tmp.php

Information Theft

This backdoor gathers the following data:

  • OS version
  • Computer name
  • Logged in user
  • List of files
  • List of directories


The component enumerates OPC servers and gathers the following information:

  • CLSIDl
  • UserType
  • Program ID
  • Version support
  • Server bandwidth
  • Server state


Minimum Scan Engine:


Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.

Step 2

Scan your computer with your Trend Micro product and note files detected as BKDR_HAVEX.A

Step 3

Restart in Safe Mode

[ Learn More ]

Step 4

Delete this registry value

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    • svcprocess = "rundll32 "%System%\svcprocess{version}.dll", RunDllEntry"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • svcprocess = "rundll32 "%System%\svcprocess{version}.dll", RunDllEntry"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\InternetRegistry
    • fertger = "{random}-{random}"

Step 5

Search and delete this file

[ Learn More ]
There may be some files that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.
  • %User Temp%\mbCHECK.exe

Step 6

Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_HAVEX.A. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.

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