Windows Tutorials - Herong's Tutorial Notes
Dr. Herong Yang, Version 4.20

Trojan and Adware - Vundo (vtsts.dll) Removal

Part:   1  2  3  4  5  6 

Windows Tutorials - Herong's Notes © 2006 Dr. Herong Yang

Adware - VSAdd-in.dll and Removal

Trojan and Adware - Vundo

Controlling IE Addons

Removing Spyware

Web Log Analysis

Paint - Graphics Tool

WinRAR - RAR Compression Tool

FTP Server and Client

Crossover Cable Network

... Table of Contents

(Continued from previous part...)

Where Is vtsts.dll Hiding?

Befor downloading any anti-virus tools, I decided to try to find and delete vtsts.dll manually.

File Explorer Checking: Using File Explorer, I could not see vtsts.dll in \windows\system32 directory.

Command Window Checking: Using Command Window, I could not see vtsts.dll in \windows\system32 directory:

>dir C:\WINDOWS\system32\vtsts.dll
   (no file)

File Explorer Checking Again: I decided to review File Explorer options to make sure it is not hiding any files:

Run File Explorer
Go to menu Tools >> Folder Options. The Folder Options dialog box displays. 
Click View tab. 
Review Advanced settings:
   Display the contents of system folders: checked
   Show hidden files and folders: checked
   Hide extensions for known file types: unchecked
   Hide protected operating system files: checked
Change the last setting to: 
   Hide protected operating system files: unchecked
Click OK to save changes

When I looked the \windows\system32 folder again, I saw vtsts.dll and several other strange files:

jkkjj.dll      557,108   12/21/2005 11:29 AM 
vtsts.dll      557,108   12/21/2005 11:30 AM
ststv.tmp        1,190   12/21/2005  5:52 PM
ststv.ini        1,236   12/31/2005 10:54 PM
ststv.bak1   1,078,661    6/18/2006 11:17 PM
ststv.bak2   1,399,968    11/3/2006 11:06 PM
ststv.ini2       1,398    11/4/2006 10:42 AM

Action: I tried the following steps to remove vtsts.dll:

1. Copy of the above suspicious files into a ZIP file, vundo_200611.zip.

2. Try to delete vtsts.dll with File Explorer. But I got a "File in use" error.

3. Try to delete vtsts.dll with HiJackThis:

Run HiJackThis
Do a system scan
Find and check the vtsts.dll entry in the scan report
Click "Fix checked" 
Do a system can again
View the scan report
   vtsts.dll entry is still in the report

Conclusion: I did not see the vtsts.dll file in the Windows system directory, because Trojan Vundo hides this file as a Windows system. So it will not show up in File Explorer window with its default setting. Actually, Trojan Vundo hides several files in the Windows system directory, like vtsts.dll, jkkjj.dll, ststv.tmp, etc., as Windows system files.

In the future, if you are search for suspicious files, remember to turn off the "Hide protected operating system files" setting in File Explorer.

Trojan Vundo file, vtsts.dll, can not be fixed by HiJackThis V1.99. I did not try any newer versions.

(Continued on next part...)

Part:   1  2  3  4  5  6 

Dr. Herong Yang, updated in 2006
Windows Tutorials - Herong's Tutorial Notes - Trojan and Adware - Vundo (vtsts.dll) Removal