WORM_GAMETHI.MBC

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

The dropped file is injected in all running processes.

It modifies registry entries to hide files with System and Read-only attributes.

It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.

It does not have any backdoor routine.

As of this writing, the said sites are inaccessible.

It steals sensitive information such as user names and passwords, particularly for certain games. Stolen information may be used for profit by cybercriminals who may gain access to the information.

It deletes the initially executed copy of itself.

Arrival Details

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

Installation

This worm drops the following file(s)/component(s):

• %User Temp%\rbking0.dll - also detected as WORM_GAMETHI.MBC

(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.)

It drops the following copies of itself into the affected system:

• %User Temp%\rbking.exe

(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.)

The dropped file is injected in all running processes.

Autostart Technique

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
king_rb = "%User Temp%\rbking.exe"

Other System Modifications

This worm modifies the following registry entries to hide files with System and Read-only attributes:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
Hidden = "2"

(Note: The default value data of the said registry entry is 1.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
ShowSuperHidden = "0"

(Note: The default value data of the said registry entry is 1.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced\Folder\Hidden\
SHOWALL
CheckedValue = "0"

(Note: The default value data of the said registry entry is 1.)

Propagation

This worm drops the following copy of itself in all physical and removable drives:

• skg1.exe

It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.

The said .INF file contains the following strings:

[AutoRun]
open=skg1.exe
shell\open\Command=skg1.exe

Backdoor Routine

This worm does not have any backdoor routine.

Process Termination

This worm terminates the following processes if found running in the affected system's memory:

• ALUSCHEDULERSVC.EXE
• ASHDISP.EXE
• AVGNT.EXE
• AVGRSX.EXE
• AVP.EXE
• AYAGENT.AYE
• AYUpdate.aye
• CCSVCHST.EXE
• EKRN.EXE
• LIVESRV.EXE
• SfFnUp.exe
• UFSEAGNT.EXE
• UfUpdUi.exe
• Update.exe
• VCRMON.EXE
• VSTSKMGR.EXE
• avast.setup
• avgupd.exe
• eguiEmon.dll
• eguiEpfw.dll
• ekrnEmon.dll
• ekrnEpfw.dll
• luall.exe
• mcupdate.exe
• preupd.exe
• prupdate.ppl
• setup.ovr
• update.exe
• updater.dll
• vsupdate.dll

Download Routine

This worm downloads an updated copy of itself from the following website(s):

• http://www.{BLOCKED}8.com/1rb/ar1.rar

As of this writing, the said sites are inaccessible.

Information Theft

This worm steals sensitive information such as user names and passwords, particularly for certain games.

Stolen Information

This worm sends the gathered information via HTTP POST to the following URL:

• {BLOCKED}8.com

Other Details

This worm deletes the initially executed copy of itself

NOTES:

This worm also injects itself to the following processes to steal sensitive information such as user names and passwords:

• ARAD.exe
• Atlantica.exe
• cabalmain.exe
• coc.exe
• explorer.exe
• iexplore.exe
• lin.bin
• maplestory.exe
• pol.exe
• Ragexe.exe
• red stone.exe

This worm also gathers user names and passwords related to the following websites:

• www.arad.jp
• arad.hangame.co.jp
• member.gungho.jp
• https://login.yahoo.co.jp/config/login_verify2?.src=ym
• https://login.yahoo.co.jp/config/login?

This worm does not have rootkit capabilities.

This worm does not exploit any vulnerability.