BKDR_MAROON.A

Malware type: Backdoor

Aliases: Trojan-Dropper.Win32.Agent.amm (Kaspersky), W32/Randon.worm.gen (McAfee), Trojan.Dropper (Symantec), DR/Hacdef.084.2 (Avira), W32/Randon-AI (Sophos),

In the wild: Yes

Destructive: No

Language: English

Platform: Windows 95, 98, ME, NT, 2000, XP

Encrypted: No

Overall risk rating:

Reported infections:

Damage potential:

High

Distribution potential:

High

Description: 

Upon execution, this memory-resident backdoor program creates a folder named D0E0T1 in the Windows system folder.

(NOTE: The Windows system folder is usually C:\Windows\System on Windows 95, 98 and ME, C:\WINNT\System32 on Windows NT and 2000, and C:\Windows\System32 on Windows XP.)

It drops the following files in the said folder:

  • CALCU.EXE (27,136 Bytes) - this file collects the list of running processes on the system
  • DIR32.EXE (25,088 Bytes) - this is an ip scanner program
  • DIROTE.EXE (566,784 Bytes) - this file is a modified mIRC application which compromises the current system. E.g., It can transform the current system into a file server to enable remote users to connect to it. Trend Micro detects this file as TROJ_BOTIRC.A
  • DOROD.EXE (46,080 Bytes) - this is an ip scanner program
  • KLTYE.EXE (37,376 Bytes) - this is a network administration tool which is also known as PSEXEC.EXE. It is used to manage remote computers.
  • KOLDER.EXE (17,408 Bytes) - this is a tool used to execute applications in stealth mode
  • ROUDSTID.EXE (175,104 Bytes) - this is a tool that scans for vulnerabilities
  • VAN32.EXE (3,568 Bytes) - this is a tool used to hide applications that are currently executing

It creates a registry entry to ensure its automatic execution at every system startup.

This worm has backdoor capabilities. It acts as a server program controlled by an IRC Bot.

Once connected, this IRC Bot is capable of sending commands to the server program. These commands are used to control the current system and the behavior of the bot.

With the IRC console, the bot inputs the commands to the console and waits to receive information from the server.

This malware runs on Windows 95, 98, ME, NT, 2000 and XP.

For additional information about this threat, see:

Description created: May. 20, 2004 11:43:21 AM GMT -0800
Description updated: May. 20, 2004 12:23:50 PM GMT -0800


TECHNICAL DETAILS


Size of malware: 1,060,906 Bytes

Initial samples received on: May 20, 2004

Payload 1: Compromises network security

Trigger condition 1: Upon execution

Details:

Arrival and Installation

Upon execution, this memory-resident backdoor program creates a folder named D0E0T1 in the Windows system folder. It drops the following files in the said folder:

  • CALCU.EXE (27,136 Bytes) - this file collects the list of running processes on the system
  • DIR32.EXE (25,088 Bytes) - this is an ip scanner program
  • DIROTE.EXE (566,784 Bytes) - this file is a modified mIRC application which compromises the current system. E.g., It can transform the current system into a file server to enable remote users to connect to it. Trend Micro detects this file as TROJ_BOTIRC.A
  • DOROD.EXE (46,080 Bytes) - this is an ip scanner program
  • KLTYE.EXE (37,376 Bytes) - this is a network administration tool which is also known as PSEXEC.EXE. It is used to manage remote computers.
  • KOLDER.EXE (17,408 Bytes) - this is a tool used to execute applications in stealth mode
  • ROUDSTID.EXE (175,104 Bytes) - this is a tool that scans for vulnerabilities
  • VAN32.EXE (3,568 Bytes) - this is a tool used to hide applications that are currently executing

Autostart Technique

It creates the following registry entry to ensure its automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\
CurrentVersion\Run
rn4d = "%System%\d0e0t1\kolder.exe %system32%\d0e0t1\dirote.exe"

NOTE: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 95, 98 and ME, C:\WINNT\System32 on Windows NT and 2000, and C:\Windows\System32 on Windows XP.

Backdoor Capabilities

This worm has backdoor capabilities. It acts as a server program controlled by an IRC Bot.

Once connected, this IRC Bot is capable of sending commands to the server program. These commands are used to control the target system and the behavior of the bot.

With the IRC console, the bot inputs the commands to the console and waits to receive information from the server.

The following are Bot commands used by the bot to control the malware server program:

  • Remotely execute a file
  • Display and retrieve system information
  • Scan system for vulnerabilities
  • Hide running applications

Other details

This malware is compressed using WinRAR.




Analysis by: Bryant Tan


SOLUTION


Minimum scan engine version needed: 6.500

Pattern file needed: 1.894.27

Pattern release date: May 20, 2004


Important note: The "Minimum scan engine" refers to the earliest Trend Micro scan engine version guaranteed to detect this threat. However, Trend Micro strongly recommends that you update to the latest version in order to get comprehensive protection. Download the latest scan engine here.

Solution:

Restarting in Safe Mode

� On Windows 95

  1. Restart your computer.
  2. Press F8 at the Starting Windows 95 message.
  3. Choose Safe Mode from the Windows 95 Startup Menu then press Enter.

� On Windows 98 and ME

  1. Restart your computer.
  2. Press the CTRL key until the Windows 98 startup menu appears.
  3. Choose the Safe Mode option then press Enter.

� On Windows NT (VGA mode)

  1. Click Start>Settings>Control Panel.
  2. Double-click the System icon.
  3. Click the Startup/Shutdown tab.
  4. Set the Show List field to 10 seconds and click OK to save this change.
  5. Shut down and restart your computer.
  6. Select VGA mode from the startup menu.

� On Windows 2000

  1. Restart your computer.
  2. Press the F8 key, when you see the Starting Windows bar at the bottom of the screen.
  3. Choose the Safe Mode option from the Windows Advanced Options Menu then press Enter.

� On Windows XP

  1. Restart your computer.
  2. Press F8 after the Power-On Self Test (POST) is done. If the Windows Advanced Options Menu does not appear, try restarting and then pressing F8 several times after the POST screen.
  3. Choose the Safe Mode option from the Windows Advanced Options Menu then press Enter.

Note: After performing all the solutions for the removal of this malware, please restart your system normally, and run your Trend Micro antivirus product.

Deleting a Malware Folder

  1. Right-click Start then click Search� or Find� depending on your version of Windows.
  2. In the Named input box, type:
    d0e0t1
  3. In the Look In drop-down list, select the drive which contains Windows, then press Enter.
  4. Once located, select the said folder then hit Delete.

Removing Autostart Entries from the Registry

Removing autostart entries from the registry prevents the malware from executing during startup.

  1. Open Registry Editor. To do this, click Start>Run, type REGEDIT, then press Enter.
  2. In the left panel, double-click the following: HKEY_LOCAL_MACHINE>Software>Microsoft>Windows>
    CurrentVersion>Run
  3. In the right panel, locate and delete the entry or entries: rn4d = "%System%\d0e0t1\kolder.exe %System%\d0e0t1\dirote.exe"
    NOTE: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 95, 98 and ME, C:\WINNT\System32 on Windows NT and 2000, and C:\Windows\System32 on Windows XP.
  4. In the left panel, double-click the following: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ordor
  5. In the left panel, locate and delete the key:
    Ordor
  6. Close Registry Editor.

Additional Windows XP Cleaning Instructions Running Trend Micro Antivirus

Scan your system with Trend Micro antivirus and delete all files detected as BKDR_MAROON.A. To do this, Trend Micro customers must download the latest pattern file and scan their system. Other users can use HouseCall, Trend Micro�s free online virus scanner.


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