Windows Tutorials - Herong's Tutorial Examples - v5.62, by Dr. Herong Yang
What Is Vundo Related vtsts.dll
This section provides a tutorial example of how to find the root file of trojan Vundo, vtsts.dll.
Of course, this time I had to do more than removing these DLL files. I had to try to find the root of this Trojan Vundo.
So I looked at the HijackThis report carefully again, examining each entry in the report and did Google search on each associated program. When I reached the following entry, I got some interested matches on Google search result:
O2 - BHO: ATLDistrib Object - {93C6313C-9DB4-4694-8BD0-E378C573A9AD} - C:\WINDOWS\system32\vtsts.dll
Google Search Result - Part I: When I searched for "vtsts.dll" with Google, I got the following interesting items out of 785 matches:
1. From www.bullguard.com/forum/8/DowloadTrojan-Virus-vtstsdll_14346.html, it's a long forum post and replies dated on May 7, 2005. The infected system has 2 related entries in its HijackThis report:
O2 - BHO: (no name) - {8E13DDE1-E013-47ec-9C4C-27C2F78BDD26} - C:\WINDOWS\system32\vtsts.dll O20 - Winlogon Notify: vtsts - C:\WINDOWS\SYSTEM32\vtsts.dll
Based on the replies, the infected system was cleaned by AVG Antivirus from www.grisoft.com, after several failed attempts from different anti-virus tools.
2. From forums.techguy.org/security/415370-solved-help-remove-downloader-trojan.html, it's a long forum post and replies date on Nov. 9, 2005. The infected system has 3 related entries in its HijackThis report:
O2 - BHO: (no name) - {00DBDAC8-4691-4797-8E6A-7C6AB89BC441} - C:\WINDOWS\system32\vtsts.dll O20 - Winlogon Notify: vtsqr - C:\WINDOWS\system32\vtsqr.dll O20 - Winlogon Notify: vtsts - C:\WINDOWS\SYSTEM32\vtsts.dll
Based on the replies, the infected system was cleaned by using VundoFix.exe from atribune.org and Killbox from subratam.org, combined with detailed guiding instructions providing by the forum moderator, Flrman1.
This tells me that vtsts.dll is related to Trojan Vundo.
3. From www.lavasoftsupport.com/lofiversion/index.php/t1570.html, it's a long forum post and replies date on Jul. 5, 2006. The infected system has 4 related entries in its HijackThis report:
O2 - BHO: (no name) - {20D57A66-F7DF-467d-907B-9B7F4A118AB7} - C:\WINDOWS\system32\mllmm.dll O2 - BHO: DosSpecFolder Object {3496D13A-609A-407B-B181-8F47B4F28AE9} - C:\WINDOWS\system32\vtsts.dll O20 - Winlogon Notify: mllmm - C:\WINDOWS\SYSTEM32\mllmm.dll O20 - Winlogon Notify: vtsts - C:\WINDOWS\system32\vtsts.dll
Removal instuctions were given to use Qoofix from malwarebytes.org and VundoFix.exe from atribune.org. But no final reply on the results of the suggested removal process on the infected system.
Google Search Result - Part II: When I searched for "ATLDistrib Object" with Google, I got the following interesting items out of 9,940 matches:
1. From wiki.castlecops.com/Malware_Removal:_Virtumundo, it's an article about Adware-Virtumundo (Vundo) removal. There are two sets of HijackThis report entries related ATLDistrib Object:
Example 1: O2 - BHO: ATLDistrib Object - {7A1A109F-58B3-414B-9829-5F4D9BE5FEDE} - C:\WINDOWS\system32\mljjj.dll O20 - Winlogon Notify: mljjj - C:\WINDOWS\system32\mljjj.dll Example 2: O2 - BHO: ATLDistrib Object - {7A1A109F-58B3-414B-9829-5F4D9BE5FEDE} - C:\WINDOWS\system32\pmnlj.dll 020 - Winlogon Notify: pmnlj - C:\WINDOWS\system32\pmnlj.dll
This confirms that vtsts.dll is related to Trojan Vundo.
2. From www.geekstogo.com/forum/index.php?showtopic=86351, it's a forum post and replies dated on Dec. 23, 2005. The infected system has 2 related entries in its HijackThis report:
O2 - BHO: ATLDistrib Object - {3FE36807-69ED-45D1-B9BE-85C0E3F75B6A} - C:\WINDOWS\System32\ddccd.dll O20 - Winlogon Notify: ddccd - C:\WINDOWS\System32\ddccd.dll
Based on the replies, the infected system was cleaned by using VundoFix.exe, WebRoot SpySweeper, VirtumundoBegone, Panda Active Scan, and Killbox, combined with detailed guiding instructions providing by the Malware Removal Specialist, loophole.
This confirms again that vtsts.dll is related to Trojan Vundo.
Conclusion: vtsts.dll and "ATLDistrib Object" are related to Trojan Vundo. I must missed the vtsts.dll entry from the HijackThis report during my last visit.
From my Google results, all reported cases are having the suspicious DLL file registered as a Winlogon Notify entry. But I could not find any similar "020" entry in my friend's HijackThis report. So this could be new variant of Trojan Vundo.
Or this is a partial broken Trojan Vundo. This seemed to match the symptom that the Internet Explorer pops up, but not showing any target Web sites, and closes up by itself.
Table of Contents
Introduction to Microsoft Windows
Introduction to Windows Explorer
Introduction to Internet Explorer
"Paint" Program and Computer Graphics
GIMP - GNU Image Manipulation Program
JPEG Image File Format Quality and Size
GIF Image File Format and Transparent Background
"WinZip" - ZIP File Compression Tool
"WinRAR" - RAR and ZIP File Compression Tool
FTP Server, Client and Commands
"FileZilla" - Free FTP Client and Server
Web Server Log Files and Analysis Tool - "Analog"
Spyware Adware Detection and Removal
IE Addon Program Listing and Removal
►Vundo (VirtuMonde/VirtuMundo) - vtsts.dll Removal
Partial Removal of Trojan Vundo
Detecting Trojan Vundo with McAfee VirusScan
Instructions on Full Removal of Trojan Vundo
Removing xxxxxxxx.dll Files Generated by Vundo
►What Is Vundo Related vtsts.dll
Finding and Removing vtsts.dll Manually
Removing Trojan Vundo with FixVundo.exe from Symantec
Removing Trojan Vundo with VundoFix.exe from Atribune.org
Trojan and Malware "Puper" Description and Removal
VSToolbar (VSAdd-in.dll) - Description and Removal
Spybot - Spyware Blocker, Detection and Removal
Setting Up and Using Crossover Cable Network
Home Network Gateway - DSL Modem/Wireless Router
Windows Task Manager - The System Performance Tool
"tasklist" Command Line Tool to List Process Information
"msconfig" - System Configuration Tool
Configuring and Managing System Services
Windows Registry Key and Value Management Tools