WORM_TATERF.FJK

This worm attempts to steal user credentials, such as user names and passwords, that are related to online games. It does this by monitoring processes/services in the memory that contains certain strings.

It also steals Yahoo! Japan credentials by monitoring certain URLs, processes, and registry key.

It deletes the initially executed copy of itself.

This Worm arrives via removable drives. It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

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 itself after execution.

Arrival Details

This Worm arrives via removable drives.

It 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 component file(s):

• %User Temp%\4tddfwq{number}.dll - also detected as WORM_TATERF.FJK

(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(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

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

• %User Temp%\xvassdf.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(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

It adds the following processes:

• iexplore.exe

It injects codes into the following process(es):

• explorer.exe
• created iexplore.exe

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
54dfsger = "%User Temp%\xvassdf.exe"

Other System Modifications

This Worm modifies the following registry entries:

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.)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
Explorer
NoDriveTypeAutoRun = "145"

(Note: The default value data of the said registry entry is "255".)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
Explorer
NoDriveTypeAutoRun = "145"

(Note: The default value data of the said registry entry is "255".)

Propagation

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

• {drive letter}:\puia6h.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=puia6h.exe
shell\open\Command=puia6h.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:

• RavMon.exe

Download Routine

This Worm accesses the following websites to download files:

• http://www.{BLOCKED}d3.com/1rb/ar1.rar

It saves the files it downloads using the following names:

• %User Temp%\ar1.rar

(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(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

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.

Other Details

This Worm closes application windows that contain the following strings in the title bar:

• AVP.AlertDialog
• AVP.Product_Notification

It deletes itself after execution.

NOTES:

This worm checks if the following processes related to antivirus products are running in memory:

• ALUSCHEDULERSVC.EXE
• ASHDISP.EXE
• AVGNT.EXE
• AVGRSX.EXE
• AVP.EXE
• AYAGENT.AYE
• CCSVCHST.EXE
• EKRN.EXE
• LIVESRV.EXE
• UFSEAGNT.EXE
• VCRMON.EXE
• VSTSKMGR.EXE

If found running, it retrieves the folder where the said files are located. It will then search for any of the following component files, depending on the antivirus process it found:

• avast.setup
• avgupd.exe
• AYUpdate.aye
• eguiEpfw.dll
• eguiEmon.dll
• ekrnEpfw.dll
• ekrnEmon.dll
• luall.exe
• mcupdate.exe
• preupd.exe
• prupdate.ppl
• setup.ovr
• SfFnUp.exe
• UfUpdUi.exe
• Update.exe
• updater.dll
• vsupdate.dll

It searches files from the said folder with the following extensions:

• .DLL
• .EXE

It then moves the files it found in %System Root% and replaces the file name with {file name}.{extension}.vcd.

It also attempts to steal user credentials, such as user names and passwords, related to online games. It does this by monitoring processes/services in the memory that contains the following strings:

• Altair(Non-PvP)
• Arcturus
• Canopus
• coc.exe
• Forthgoer
• pol.exe
• Ragexe.exe
• Rigel
• Sirius
• Vega(Non-PvP)

It attempts to steal information from the following file if present on the affected system:

• aaa.dat

It also steals Yahoo! Japan credentials by monitoring the following URLs, processes, and registry keys:

• https://{BLOCKED}n.{BLOCKED}o.co.jp/config/login_verify2?.src=ym
• https://{BLOCKED}n.{BLOCKED}o.co.jp/config/login?
• YahooWidgetEngine.exe
• YPagerj.exe
• \Software\YahooJapan