clicking search page links,
results in randomly redirected URL pages
svchost.exe and rundll32.exe used to load malware/spyware DLL
Today, for the second time in a month, I was asked to help remove a spyware/malware from a computer running Windows XP SP3. In both cases, the symptoms were identical. The user immediately noticed something was wrong because their web browser started to behave oddly. Here is what happened:
- Open the web browser of choice (IE or Firefox or Opera) and load a search portal (Google, MSN or Yahoo) site
- type in something to search (“winter coat”)
- on the results page, if you right-click on a link and “open in new tab/window”, the page opens and immediately gets redirected to some other random page (usually some other portal site)
- HOWEVER, if you right-click on a link and select “copy shortcut”, then MANUALLY open a tab and paste the link, the page opens just fine
The first time this happened (Feb. 3, 2010), it was on a friend’s computer and he is a veteran IT person (network system administrator for 10+ years). He keeps his computer very secure, usually.
We checked the usual system settings (network settings, proxy settings, “odd” programs running, etc.). We ran the usual anti-spyware and anti-virus scans, call came back clean as usual.
Avast AntiVirus – clean
ClamAV – clean
HiJackThis – normal
MalwareBytes – clean
Spybot SD – clean
However, running the SysInternals utility, PROCEXP.EXE, I happened to notice this line:
C:\WINDOWS\system32\rundll32.exe “C:\WINDOWS\system32\efsadub.dll”,DWLGXPLFFX
which was running as a sub-process under svchost.exe (C:\WINDOWS\system32\svchost.exe -k netsvcs).
The file “C:\WINDOWS\system32\efsadub.dll” (notice the “b” in the filename) had its special bits set as “read-only”, “hidden” and “system”. When we try to change the attributes, we get “Access Denied” (even from an Administrator account). Hell, we even tried to access this in Safe-Mode Command Prompt Only, we get the same error. We could not rename the file either, obviously.
I was finally able to change the attributes and rename the file after running “
For the VirusTotal analysis report on the file “efsadub.dll“, goto:
http://www.virustotal.com/analisis/b1ff584a9b490418a159ab4afe85ae1802e4c4634c942756640a4411467ef25d-1264975725
Today (March 5, 2010), a client called and his computer had the same symptoms. Again, I checked the usual suspects (running programs, etc.) and performed the usual scans (anti-virus, anti-malware, etc.). They all came back “clean”. However, I did notice that the signatures were slightly dated (about a month old). When I tried to update them, error messages resulted. MalwareBytes gave an error and hung in a loop. Symantec Anti-Virus LiveUpdates just failed.
ClamAV – clean
MalwareBytes – clean
Symantec Anti-Virus – clean
I then ran the PROCEXP.EXE utility from SysInternals. There were no odd DLLs loaded like the last time. Hmm… so this is not exactly the same as last time.
Since this had to be a malware that loaded at startup, I decided to check the System Services. I then noticed an “odd” service running named “Server WebCheckChannelAgent Performance Folder Provisioning Icon Driver CPL”, with a short-name of “srvoko6”. I tried to disable it and it kept resetting to “Automatic”.
Looking at the properties of this service, revealed that it was loading via “%SYSTEM%\svchost.exe –k netsvc6”. I searched the web on the terms “srvoko6” and “netsvc6”, I came across this site:
http://www.threatexpert.com/report.aspx?md5=c801bd4576fc95cb03e918950edd21a1
which mentions the “ok6o.dll” and “ok6o.sys” files. So I searched for those files, and found them (they were not hidden). Trying to rename them worked, but they were immediately recreated by the malware.
NOTE: the above ThreatExpert site reports that this service was also named “Office Workstation Remote”. This tells me that the service display name can vary.
Instead, I used “CACLS.EXE” to change access permissions to these files so that nobody (or system service) was allowed to access them. Rebooted the computer and verified that the malware was no longer actively running. This time, I was able to successfully disable the service and renamed the “ok6o.dll” and “ok6o.sys” files.
I was then able to restore permissions to those files and delete them. Updated signatures for MalwareBytes and Symantec Anti-Virus, followed by a complete system scan. This time those programs found the installer stub files “C:\WINDOWS\bill103.exe” and “C:\WINDOWS\rdr_1267369102.exe” (which most likely are random filenames the initial download script created).
For the VirusTotal analysis on the file “o6ko.dll“, goto:
http://www.virustotal.com/analisis/7d6d2edc4eac763bc687e578008474dc85245b1e55d5ca5ae958d220f4802fbf-1267641995
For the VirusTotal analysis on the file “o6ko.sys“, goto:
http://www.virustotal.com/analisis/d599b5fb31b6387ff7e540fabb655bbde0990ce9db1e6f1918bec6ac21d43278-1267374431
As you can see from the VirusTotal analysis reports, not all anti-virus scanners detect or flag these files. So, for most of these malware/spyware, it still requires manual detection and removal.
STRONG WARNING: be very careful of websites that tells you do download an executable to remove the malware/spyware. If you are not familiar with the website, DO NOT download and run the program, it can possibly install another piece of malwayre/spyware onto your computer. It is best to call a professional (or at least someone who knows with 100% certainty what they are doing) to clean your computer.
NOTICE: when renaming files and changing attributes or permissions, it is strongly advised that you do those via command-line commands in the “Command Prompt” window. If the malware/spyware is attached to the Windows Explorer process and/or its handles, it can intercept your mouse-click commands, making it seem like you did what you wanted to, but in reality the malware/spyware actually created another copy of itself with a different name and reinstalled itself using those new copies. The “Command Prompt” method is the most secure way of doing this work; however it is a lot of typing.
Feel free to post comments below if you need help or have recommendations.
©2010 Johnny Chin. All Rights Reserved.
clicking search page links,
results in randomly redirected URL pages
svchost.exe and rundll32.exe used to load malware/spyware DLL
Today, for the second time in a month, I was asked to help remove a spyware/malware from a computer running Windows XP SP3. In both cases, the symptoms were identical. The user immediately noticed something was wrong because their web browser started to behave oddly. Here is what happened:
- Open the web browser of choice (IE or Firefox or Opera) and load a search portal (Google, MSN or Yahoo) site
- type in something to search (“winter coat”)
- on the results page, if you right-click on a link and “open in new tab/window”, the page opens and immediately gets redirected to some other random page (usually some other portal site)
- HOWEVER, if you right-click on a link and select “copy shortcut”, then MANUALLY open a tab and paste the link, the page opens just fine
The first time this happened (Feb. 3, 2010), it was on a friend’s computer and he is a veteran IT person (network system administrator for 10+ years). He keeps his computer very secure, usually.
We checked the usual system settings (network settings, proxy settings, “odd” programs running, etc.). We ran the usual anti-spyware and anti-virus scans, call came back clean as usual.
Avast AntiVirus – clean
ClamAV – clean
HiJackThis – normal
MalwareBytes – clean
Spybot SD – clean
However, running the SysInternals utility, PROCEXP.EXE, I happened to notice this line:
C:\WINDOWS\system32\rundll32.exe “C:\WINDOWS\system32\efsadub.dll”,DWLGXPLFFX
which was running as a sub-process under svchost.exe (C:\WINDOWS\system32\svchost.exe -k netsvcs).
The file “C:\WINDOWS\system32\efsadub.dll” (notice the “b” in the filename) had its special bits set as “read-only”, “hidden” and “system”. When we try to change the attributes, we get “Access Denied” (even from an Administrator account). Hell, we even tried to access this in Safe-Mode Command Prompt Only, we get the same error. We could not rename the file either, obviously.
I was finally able to change the attributes and rename the file after running “
For the VirusTotal analysis report on the file “efsadub.dll“, goto:
http://www.virustotal.com/analisis/b1ff584a9b490418a159ab4afe85ae1802e4c4634c942756640a4411467ef25d-1264975725
Today (March 5, 2010), a client called and his computer had the same symptoms. Again, I checked the usual suspects (running programs, etc.) and performed the usual scans (anti-virus, anti-malware, etc.). They all came back “clean”. However, I did notice that the signatures were slightly dated (about a month old). When I tried to update them, error messages resulted. MalwareBytes gave an error and hung in a loop. Symantec Anti-Virus LiveUpdates just failed.
ClamAV – clean
MalwareBytes – clean
Symantec Anti-Virus – clean
I then ran the PROCEXP.EXE utility from SysInternals. There were no odd DLLs loaded like the last time. Hmm… so this is not exactly the same as last time.
Since this had to be a malware that loaded at startup, I decided to check the System Services. I then noticed an “odd” service running named “Server WebCheckChannelAgent Performance Folder Provisioning Icon Driver CPL”, with a short-name of “srvoko6”. I tried to disable it and it kept resetting to “Automatic”.
Looking at the properties of this service, revealed that it was loading via “%SYSTEM%\svchost.exe –k netsvc6”. I searched the web on the terms “srvoko6” and “netsvc6”, I came across this site:
http://www.threatexpert.com/report.aspx?md5=c801bd4576fc95cb03e918950edd21a1
which mentions the “ok6o.dll” and “ok6o.sys” files. So I searched for those files, and found them (they were not hidden). Trying to rename them worked, but they were immediately recreated by the malware.
NOTE: the above ThreatExpert site reports that this service was also named “Office Workstation Remote”. This tells me that the service display name can vary.
Instead, I used “CACLS.EXE” to change access permissions to these files so that nobody (or system service) was allowed to access them. Rebooted the computer and verified that the malware was no longer actively running. This time, I was able to successfully disable the service and renamed the “ok6o.dll” and “ok6o.sys” files.
I was then able to restore permissions to those files and delete them. Updated signatures for MalwareBytes and Symantec Anti-Virus, followed by a complete system scan. This time those programs found the installer stub files “C:\WINDOWS\bill103.exe” and “C:\WINDOWS\rdr_1267369102.exe” (which most likely are random filenames the initial download script created).
For the VirusTotal analysis on the file “o6ko.dll“, goto:
http://www.virustotal.com/analisis/7d6d2edc4eac763bc687e578008474dc85245b1e55d5ca5ae958d220f4802fbf-1267641995
For the VirusTotal analysis on the file “o6ko.sys“, goto:
http://www.virustotal.com/analisis/d599b5fb31b6387ff7e540fabb655bbde0990ce9db1e6f1918bec6ac21d43278-1267374431
As you can see from the VirusTotal analysis reports, not all anti-virus scanners detect or flag these files. So, for most of these malware/spyware, it still requires manual detection and removal.
STRONG WARNING: be very careful of websites that tells you do download an executable to remove the malware/spyware. If you are not familiar with the website, DO NOT download and run the program, it can possibly install another piece of malwayre/spyware onto your computer. It is best to call a professional (or at least someone who knows with 100% certainty what they are doing) to clean your computer.
NOTICE: when renaming files and changing attributes or permissions, it is strongly advised that you do those via command-line commands in the “Command Prompt” window. If the malware/spyware is attached to the Windows Explorer process and/or its handles, it can intercept your mouse-click commands, making it seem like you did what you wanted to, but in reality the malware/spyware actually created another copy of itself with a different name and reinstalled itself using those new copies. The “Command Prompt” method is the most secure way of doing this work; however it is a lot of typing.
Feel free to post comments below if you need help or have recommendations.
I just upgraded to Firefox 3.5 and realized that Microsoft snuck in (spyware-like installation, without user acknowledgment) an extension to Firefox 3.0 that is not compatible with Firefox 3.5, that extension is the Microsoft .NET Framework Assistant 1.0.
Microsoft has released a newer version of that extension, version 1.1, which is compatible with Firefox 3.5. However, Firefox 3.5 cannot automatically update to it, you have to do it manually and can be found here:
https://addons.mozilla.org/en-US/firefox/addon/9449
Well … being that I want to use Firefox and stay away from Microsoft’s browser and plug-ins, I wanted to find a way to remove the Microsoft .NET Framework Assistant 1.0 extension, since you cannot just click “Uninstall” like all the other extensions I have in Firefox. Besides, why would I want to keep an extension installed that I did not install myself? Would you knowingly keep a piece of spyware running on your computer? Heck no!
So digging around, I found clues on how to remove it. Here is a script that I wrote to remove the extension from the computer and remove it from Firefox. However, I still had to manually remove the additional information Microsoft added to the Firefox UserAgent header.
@echo off
echo Removing dotNET Assistant Extension files …
rd /s “%windir%\Microsoft.NET\Framework\v3.5\Windows Presentation Foundation\DotNetAssistantExtension”
echo.
echo Removing dotNET extension from registry …
REG.EXE DELETE “HKLM\SOFTWARE\Mozilla\Firefox\Extensions” /v “{20a82645-c095-46ed-80e3-08825760534b}” /f
echo.
echo.
echo MUST manually remove the UserAgent setting from each Firefox profile …
echo.
echo you can manually delete this line from each prefs.js:
echo user_pref(“general.useragent.extra.microsoftdotnet”, “(.NET CLR 3.5.30729)”);
echo.
echo or do it from “about:config” within Firefox
echo.
However, this code did NOT work for all of my workstations. I found that in those cases I needed to manually remove an entry from the registry, so I created this .REG file:
REGEDIT4[HKEY_LOCAL_MACHINE\SOFTWARE\Mozilla\Firefox\extensions]
“{20a82645-c095-46ed-80e3-08825760534b}”=-
Finally, to remove the added text from the UserAgent header in Firefox.
One way to do this is to simply open the prefs.js for your Firefox profile and remove the line which reads:
user_pref(“general.useragent.extra.microsoftdotnet”, “(.NET CLR 3.5.30729)”);
Or you can … in Firefox, type “about:config” into the URL box and you should see this:
Now in the filter box, type “useragent” and you should see something like this:
Right-click on the “general.useragent.extra.microsoftdotnet” line brings up a menu, select “Reset”.
Now close out of Firefox completely and restart it. You are now done.
Reference: http://support.microsoft.com/kb/963707
©2010 Johnny Chin. All Rights Reserved.
I just upgraded to Firefox 3.5 and realized that Microsoft snuck in (spyware-like installation, without user acknowledgment) an extension to Firefox 3.0 that is not compatible with Firefox 3.5, that extension is the Microsoft .NET Framework Assistant 1.0.
Microsoft has released a newer version of that extension, version 1.1, which is compatible with Firefox 3.5. However, Firefox 3.5 cannot automatically update to it, you have to do it manually and can be found here:
https://addons.mozilla.org/en-US/firefox/addon/9449
Well … being that I want to use Firefox and stay away from Microsoft’s browser and plug-ins, I wanted to find a way to remove the Microsoft .NET Framework Assistant 1.0 extension, since you cannot just click “Uninstall” like all the other extensions I have in Firefox. Besides, why would I want to keep an extension installed that I did not install myself? Would you knowingly keep a piece of spyware running on your computer? Heck no!
So digging around, I found clues on how to remove it. Here is a script that I wrote to remove the extension from the computer and remove it from Firefox. However, I still had to manually remove the additional information Microsoft added to the Firefox UserAgent header.
@echo off
echo Removing dotNET Assistant Extension files …
rd /s “%windir%\Microsoft.NET\Framework\v3.5\Windows Presentation Foundation\DotNetAssistantExtension”
echo.
echo Removing dotNET extension from registry …
REG.EXE DELETE “HKLM\SOFTWARE\Mozilla\Firefox\Extensions” /v “{20a82645-c095-46ed-80e3-08825760534b}” /f
echo.
echo.
echo MUST manually remove the UserAgent setting from each Firefox profile …
echo.
echo you can manually delete this line from each prefs.js:
echo user_pref(“general.useragent.extra.microsoftdotnet”, “(.NET CLR 3.5.30729)”);
echo.
echo or do it from “about:config” within Firefox
echo.
However, this code did NOT work for all of my workstations. I found that in those cases I needed to manually remove an entry from the registry, so I created this .REG file:
REGEDIT4[HKEY_LOCAL_MACHINE\SOFTWARE\Mozilla\Firefox\extensions]
“{20a82645-c095-46ed-80e3-08825760534b}”=-
Finally, to remove the added text from the UserAgent header in Firefox.
One way to do this is to simply open the prefs.js for your Firefox profile and remove the line which reads:
user_pref(“general.useragent.extra.microsoftdotnet”, “(.NET CLR 3.5.30729)”);
Or you can … in Firefox, type “about:config” into the URL box and you should see this:
Now in the filter box, type “useragent” and you should see something like this:
Right-click on the “general.useragent.extra.microsoftdotnet” line brings up a menu, select “Reset”.
Now close out of Firefox completely and restart it. You are now done.
Reference: http://support.microsoft.com/kb/963707
Why does Microsoft make it so difficult to find the links to download Internet Explorer 8 as a standalone installer? It use to be at the bottom of the stub-installer download page. Well after some digging, I found them and here are direct links to the standalone off-line installers of the release version of Internet Explorer 8.
Download links below are for the United States English version of Internet Explorer 8. Click on a link below to download for the operating system of your choice:
- Windows XP (32-bit)
- Windows XP (64-bit)
- Windows Vista (32-bit)
- Windows Vista 64-bit
- Windows Server 2003 (32-bit)
- Windows Server 2003 64-bit
- Windows Server 2008 (32-bit)
- Windows Server 2008 64-bit
If you want to download a localized versions of IE8 (other languages, etc), you can download them from here.
I needed these standalone installers for a client who wanted to upgrade all their workstations to Internet Explorer 8. 
Personally, I still prefer to use Mozilla Firefox.
©2010 Johnny Chin. All Rights Reserved.
Why does Microsoft make it so difficult to find the links to download Internet Explorer 8 as a standalone installer? It use to be at the bottom of the stub-installer download page. Well after some digging, I found them and here are direct links to the standalone off-line installers of the release version of Internet Explorer 8.
Download links below are for the United States English version of Internet Explorer 8. Click on a link below to download for the operating system of your choice:
- Windows XP (32-bit)
- Windows XP (64-bit)
- Windows Vista (32-bit)
- Windows Vista 64-bit
- Windows Server 2003 (32-bit)
- Windows Server 2003 64-bit
- Windows Server 2008 (32-bit)
- Windows Server 2008 64-bit
If you want to download a localized versions of IE8 (other languages, etc), you can download them from here.
I needed these standalone installers for a client who wanted to upgrade all their workstations to Internet Explorer 8. Personally, I still prefer to use Mozilla Firefox.