Analysis by: Sabrina Lei Sioting


Windows 2000, XP, Server 2003


  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes


This backdoor may be dropped by other malware.


File Size: 148,480 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 06 Apr 2011
Payload: Drops files

Arrival Details

This backdoor may be dropped by the following malware:



This backdoor drops the following files:

  • %system root%\Documents and Settings\All Users\bootstat.dat
  • %WINDOWS%\mjRemote.dll.bak

Autostart Technique

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

mj = Rundll32.EXE %WINDOWS%\mjRemote.dll,GetClassObject


Minimum Scan Engine: 8.900

Step 1

For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

Step 2

Remove malware files dropped/downloaded by BKDR_IRCBOT.KER


Step 3

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.

Step 4

Search and delete this file

[ Learn More ]
There may be some component 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.
%system root%\Documents and Settings\All Users\bootstat.dat

Step 5

Scan your computer with your Trend Micro product to delete files detected as BKDR_IRCBOT.KER. 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.

Did this description help? Tell us how we did.