Malware type: Trojan

Aliases: Trojan-Dropper.Win32.Delf.m (Kaspersky), MultiDropper-BN (McAfee), Backdoor.Trojan.dr (Symantec), TR/Dldr.Sma.dat.4.B (Avira), Troj/Mdrop-BN (Sophos), TrojanDropper:Win32/Delf.M (Microsoft)

In the wild: No

Destructive: No

Language: English

Platform: Windows 9x/NT/2000/ME

Encrypted: No

Overall risk rating:

This Trojan Dropper drops and runs files detected by Trend Micro as BKDR_GSPOT20.A, TROJ_PSW_KUANG.C and TROJ_FAISAL.A.

For additional information about this threat, see:

Description created: Oct. 19, 2002 2:18:29 PM GMT -0800
Description updated: Oct. 22, 2002 10:00:24 AM GMT -0800


Size of malware: 291,328 Bytes

Initial samples received on: Oct 19, 2002


Upon execution, this Trojan dropper drops the files below in C:\Windows folder. Some of these files are Trojans.

  • Spool32.exe
  • winfile32.dll
  • winfile64.dll
  • winfileb32.dll
  • SYSTEM\gbot.exe
  • SYSTEM\K2ps_full.exe
  • SYSTEM\K2ps_full.dll
  • TEMP\carrace.swf
  • TEMP\gbot.exe
  • TEMP\K2pS_FULL.exe
  • TEMP\Net-server.exe

SPOOL32.EXE is an edited old copy of Spooler Sub System Process program of Windows. This file is used by the Trojans dropped.

WINFILE32.DLL is a log file containing the keys pressed by the user.

WINFILE64.DLL is one of the Trojans dropped. Trend detects this file as TROJ_FAISAL.A.

WINFILEB32.DLL is an empty file.

GBOT.EXE is one of the Trojans dropped. Trend Micro detects this backdoor file as BKDR_GSPOT20.A.

K2PS_FULL.EXE is one of the Trojans dropped. It uses K2PS_FULL.DLL as its DLL file. Trend Micro detects these two files as TROJ_PSW_KUANG.C.

NET-SERVER.EXE is a program that is used by GBOT.EXE as a keylogger.

Upon execution, This trojan dropper executes these files and displays the following window:

Upon execution TROJ_JUNTADOR.K displays a window with the title Computer Spy, clicking the install button causes the entries to be added in the registry

Clicking on the Install button causes these entries to be added in the registry:


innss "1"



These registry entries below are added to ensure that the Trojans are executed upon Windows startup:

Driver "C:\WINDOWS\SYSTEM\gbot.exe"

K2ps_full.task "C:\WINDOWS\SYSTEM\K2ps_full.exe"

Another registry entry is added, but is not related to the Trojan files.

System "YPager.exe"

These registry entries below are added to ensure that SPOOL32.EXE is executed everytime an EXE file is opened:

@ ""%1" %*" ""C:\WINDOWS\SPOOL32" %1 %*"

@ ""%1" %*" ""C:\WINDOWS\SPOOL32" %1 %*"


Minimum scan engine version needed: 5.200

Pattern file needed: 1.368.50

Pattern release date: Oct 19, 2002

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.


Terminating the Malware Program

This procedure terminates the running malware process from memory. You will need the name(s) of the file(s) detected earlier.

  1. Open Windows Task Manager.
    On Windows 9x/ME systems, press
    On Windows NT/2000/XP systems, press
    CTRL%20SHIFT%20ESC, and click the Processes tab.
  2. In the list of running programs*, locate the process:
  3. Select the malware process, then press either the End Task or the End Process button, depending on the version of Windows on your system.
  4. Do the same for all detected malware files in the list of running processes.
  5. To check if the malware process has been terminated, close Task Manager, and then open it again.
  6. Close Task Manager.

*NOTE: On systems running Windows 9x/ME, Task Manager may not show certain processes. You may use a third party process viewer to terminate the malware process. Otherwise, continue with the next procedure, noting additional instructions.

Removing Autostart Entries from the Registry

Removing autostart entries from registry prevents the malware from executing during startup. You will need the name(s) of the file(s) detected earlier.

  1. Open Registry Editor. To do this, click Start>Run, type REGEDIT, then press Enter.
  2. In the left panel, double-click the following:
  3. In the right panel, locate and delete the entries:
  4. You need to remove other entries to erase traces of this Trojan from the registry.In the left panel, double-click the following:
  5. In the right panel, locate and delete the entry:

Addressing Registry Shell Spawning

Registry shell spawning executes the malware when a user tries to run an EXE file. The following procedures should restore the registry to its original settings. With the Registry Editor still open, follow this next procedure:

  1. In the left panel, double-click the following:
  2. In the right panel, locate the registry entry:
  3. Check whether the value is SPOOL32.EXE. If so, right-click Default and select Modify to change its value.
  4. In the Value data input box, delete the existing value and type the default value:"%1" %
  5. Repeat this procedure for this registry key:
  6. Close Registry Editor.

NOTE: If you were not able to terminate the malware process from memory as described in the previous procedure, restart your system.

Removing Dropped Files

Using Windows Explorer, locate the following dropped files in their respective folders, and delete them:

  • C:\WINDOWS\Spool32.exe
  • C:\WINDOWS\winfile32.dll
  • C:\WINDOWS\winfile64.dll
  • C:\WINDOWS\winfileb32.dll
  • C:\WINDOWS\SYSTEM\gbot.exe
  • C:\WINDOWS\SYSTEM\K2ps_full.exe
  • C:\WINDOWS\SYSTEM\K2ps_full.dll
  • C:\WINDOWS\TEMP\carrace.swf
  • C:\WINDOWS\TEMP\gbot.exe
  • C:\WINDOWS\TEMP\Net-server.exe

Running Trend Micro Antivirus

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

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