This Trojan uses social engineering methods to lure users into performing certain actions that may, directly or indirectly, cause malicious routines to be performed. Specifically, it makes use of deceptive file names of the attachment of spammed email messages to lure users into clicking them.
To get a one-glance comprehensive view of the behavior of this Trojan, refer to the Threat Diagram shown below.

This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users.
It executes then deletes itself afterward.
It disables Task Manager, Registry Editor, and Folder Options.
It displays fake alerts that warn users of infection. It also displays fake scanning results of the affected system. It then asks for users to purchase it once scanning is completed. If users decide to purchase the rogue product, users are directed to a certain website asking for sensitive information, such as credit card numbers.
Arrival Details
This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users.
Installation
This Trojan drops the following file(s)/component(s):
- %User Temp%\wscsvc32.exe
- %User Temp%\topwesitjh
- %User Temp%\wmsdk64_32.exe
- %User Temp%\expand32xp.dll
(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)
It drops the following non-malicious file:
(Note: %Favorites% is the Favorites folder, where it usually is C:\Documents and Settings\{user name}\Favorites on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\Favorites on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)
Its DLL component is injected to the following process(es):
It executes then deletes itself afterward.
Autostart Technique
This Trojan adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
wmsdk64_32.exe = %Temp%\wmsdk64_32.exe
Other System Modifications
This Trojan adds the following registry entries as part of its installation routine:
HKEY_USERS\.DEFAULT\Software\
Microsoft\Internet Explorer\Main\
featurecontrol\feature_enable_ie_compression
svchost.exe = 1
HKEY_CURRENT_USER\Printers\Connections
affid = {random numbers}
HKEY_CURRENT_USER\Printers\Connections
subid = {random strings}
HKEY_CURRENT_USER\Printers\Connections
time = {variable number}
It modifies the following registry key(s)/entry(ies) as part of its installation routine:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\wscsvc
Start = 4
(Note: The default value data of the said registry entry is 2.)
It creates the following registry entry(ies) to disable Task Manager, Registry Tools and Folder Options:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
System
DisableTaskMgr = 1
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
system
DisableTaskMgr = 1
Download Routine
This Trojan connects to the following URL(s) to download its component file(s):
- http://www.{BLOCKED}hfertile.com/a/ad
- http://{BLOCKED}ofon.com/any3/5-direct.ex
- http://{BLOCKED}tycscredit.com
Adware Routine
This Trojan connects to the following URL(s) to display ads on the affected system:
- http://www.{BLOCKED}hfertile.com/a/ad
- http://{BLOCKED}ofon.com/any3/5-direct.ex
- http://{BLOCKED}tycscredit.com
Rogue Antivirus Routine
This Trojan displays fake alerts that warn users of infection. It also displays fake scanning results of the affected system. It then asks for users to purchase it once scanning is completed. If users decide to purchase the rogue product, users are directed to a certain website asking for sensitive information, such as credit card numbers.
Step 1
Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.
Step 2
Restart in Safe Mode
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To restart in Safe Mode:
• For Windows 2000 users
- Restart your computer.
- Press F8 when you see the Starting Windows bar at the bottom of the screen.
- Choose the Safe Mode option from the Windows Advanced Options menu then press Enter.
• For Windows XP users
- Restart your computer.
- Press F8 after the Power-On Self Test (POST) routine is done. If the Windows Advanced Options menu does not appear, try restarting then pressing F8 several times when the POST screen appears.
- Choose the Safe Mode option from the Windows Advanced Options menu then press Enter.
• For Windows Server 2003 users
- Restart your computer.
- Press F8 after Windows starts up. If the Windows Advanced Options menu does not appear, try restarting again and pressing F8 several times afterward.
- On the Windows Advanced Option menu, use the arrow keys to select Safe Mode then press Enter.
• For Windows Vista, Windows 7, and Windows Server 2008 users
- Restart your computer.
- Press F8 after the Power-On Self Test (POST) routine is done. If the Advanced Boot Options menu does not appear, try restarting and then pressing F8 several times after the POST screen is displayed.
- On the Advanced Boot Options menu, use the arrow keys to select the Safe Mode option, and then press Enter.
• For Windows 8, Windows 8.1, and Windows Server 2012 users
- Access the Charms bar by moving your mouse pointer to the upper right corner of the screen.
- Move your mouse pointer down and click Settings>Change your PC Settings.
- In the left panel, click General.
- In the right panel, scroll down to the bottom to find the Advanced startup section, then click the Restart now button and wait for the system to restart.
- In the Advanced Startup menu, click Troubleshoot>Advanced Options>Startup Settings>Restart and wait for the system to restart.
- In the Startup Settings menu, press 4 to enable safe mode.
Step 3
Delete this registry value
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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.
- In HKEY_CURRENT_USER\Printers\Connections
- In HKEY_CURRENT_USER\Printers\Connections
- In HKEY_CURRENT_USER\Printers\Connections
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\System
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- wmsdk64_32.exe = %Temp%\wmsdk64_32.exe
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\system
- In HKEY_USERS\.DEFAULT\Software\Microsoft\Internet Explorer\Main\featurecontrol\feature_enable_ie_compression
To delete the registry value this malware/grayware created:
- Open Registry Editor.
» For Windows 2000, Windows XP, and Windows Server 2003 users, click Start>Run, type regedit in the text box provided, and then press Enter.
» For Windows Vista, Windows 7, and Windows Server 2008 users, click the Start button, type regedit in the Search input field then press Enter.
» For Windows 8, Windows 8.1, and Windows Server 2012 users, right-click on the lower-left corner of the screen, click Run, type regedit in the text box provided, and then press Enter. - In the left panel, double-click the following:
HKEY_CURRENT_USER>Printers>Connections - In the right panel, locate and delete the entry:
affid = {random name} - Again In the right panel, locate and delete the entry:
subid = {random string} - Again In the right panel, locate and delete the entry:
time = {random number} - In the left panel, double-click the following:
HKEY_CURRENT_USER>Software>Microsoft>Windows>CurrentVersion>Policies>System - In the right panel, locate and delete the entry:
DisableTaskMgr = 1 - In the left panel, double-click the following:
HKEY_CURRENT_USER>Software>Microsoft>Windows>CurrentVersion>Run - In the right panel, locate and delete the entry:
wmsdk64_32.exe = %Temp%\wmsdk64_32.exe - In the left panel, double-click the following:
HKEY_LOCAL_MACHINE>SOFTWARE>Microsoft>Windows>CurrentVersion>policies>system - In the right panel, locate and delete the entry:
DisableTaskMgr = 1 - In the left panel, double-click the following:
HKEY_USERS>.DEFAULT>Software>Microsoft>Internet Explorer>Main>featurecontrol>feature_enable_ie_compression - In the right panel, locate and delete the entry:
svchost.exe = 1 - Close Registry Editor.
Step 4
Restore these modified registry values
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Important:Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this only if you know how to or you can seek your system administrator's help. You may also check out this Microsoft article first before modifying your computer's registry.
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\wscsvc
To restore registry values this malware/grayware modified:
- Open Registry Editor. To do this:
- On Windows 2000, XP, and Server 2003:
Click Start>Run, type REGEDIT in the text box provided, and then press Enter. - On Windows Vista, 7, and Server 2008:
Click the Start button, type REGEDIT in the Search input field then press Enter. - On Windows 8, 8.1, and Server 2012:
Right-click on the lower left corner of the screen and click Run, type REGEDIT in the Run input field, and then press Enter.
- In the left panel, double-click the following:
HKEY_LOCAL_MACHINE>SYSTEM>CurrentControlSet>Services>wscsvc - In the right panel, locate the registry value:
Start = 4 - Right-click on the value name and choose Modify. Change the value data of this entry to:
Start = 2 - Close Registry Editor.
Step 5
Search and delete these components
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There may be some components 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.
- %Favorites%\_favdata.dat
- %User Temp%\wscsvc32.exe
- %User Temp%\topwesitjh
- %User Temp%\wmsdk64_32.exe
- %User Temp%\expand32xp.dll
To manually delete a malware/grayware file from an affected system:
• For Windows 2000, Windows XP, and Windows Server 2003:
- Right-click Start then click Search....
- In the File name* input box, type the following:
- %Favorites%\_favdata.dat
- %User Temp%\wscsvc32.exe
- %User Temp%\topwesitjh
- %User Temp%\wmsdk64_32.exe
- %User Temp%\expand32xp.dll
- In the Look In drop-down list, select My Computer then press Enter.
- Once located, select the file then press SHIFT+DELETE to delete it.
*Note: The file name input box title varies depending on the Windows version (e.g. Search for files or folders named or All or part of the file name.).
• For Windows Vista, Windows 7, Windows Server 2008, Windows 8, Windows 8.1, and Windows Server 2012:
- Open a Windows Explorer window.
- For Windows Vista, 7, and Server 2008 users, click Start>Computer.
- For Windows 8, 8.1, and Server 2012 users, right-click on the lower left corner of the screen,then click File Explorer.
- In the Search Computer/This PC input box, type:
- %Favorites%\_favdata.dat
- %User Temp%\wscsvc32.exe
- %User Temp%\topwesitjh
- %User Temp%\wmsdk64_32.exe
- %User Temp%\expand32xp.dll
- Once located, select the file then press SHIFT+DELETE to delete it.
*Note: Read the following Microsoft page if these steps do not work on Windows 7.
Step 6
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_FRAUDLO.LO. 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.
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