win32: Malware-Gen please help

[hillan7]

i have read across this forum looking for a solution to the win32: Malware gen and as to why my avast is going crazy with alerts. i ran a scan with both malware bytes and OTL. the logs are attached. can anyone please help me with this issue? i really appreciate your help in this matter

[Pondus]

also attach aswMBR log...

help is on the way   

[hillan7]

the aswMBR log has been attached

[essexboy]

Warning This fix is only relevant for this system and no other, using on another computer may cause problems

Be advised that when the fix commences it will shut down all running processes and you may lose the desktop and icons, they will return on reboot

Run OTL

• Under the Custom Scans/Fixes box at the bottom, paste in the following
  
  
  

  :Files
  C:\Windows\Installer\{20fa01a6-6ca3-76b8-dd04-f9158b9a21b1}
  C:\Users\brandon\AppData\Local\{20fa01a6-6ca3-76b8-dd04-f9158b9a21b1}
  C:\Windows\assembly\GAC_32\Desktop.ini
  C:\Windows\assembly\GAC_64\Desktop.ini
  
  :Commands
  [purity]
  [resethosts]
  [emptytemp]
  [CREATERESTOREPOINT]
  [Reboot]
• Then click the Run Fix button at the top
  
• Let the program run unhindered, reboot the PC when it is done
• Open OTL again and click the Quick Scan button. Post the log it produces in your next reply.

THEN

Download and Install Combofix
 
Download ComboFix from one of the following locations:
Link 1
Link 2
 
VERY IMPORTANT !!! Save ComboFix.exe to your Desktop
 
* IMPORTANT - Disable your AntiVirus and AntiSpyware applications, usually via a right click on the System Tray icon. They may otherwise interfere with our tools. If you have difficulty properly disabling your protective programs, refer to this link here

• Double click on ComboFix.exe & follow the prompts.
  
• Accept the disclaimer and allow to update if it asks

• When finished, it shall produce a log for you.
• Please include the C:\ComboFix.txt in your next reply.[/b]
  

Notes:
1. Do not mouse-click Combofix's window while it is running. That may cause it to stall.
2. Do not "re-run" Combofix. If you have a problem, reply back for further instructions.
3.  If after the reboot you get errors about programmes being marked for deletion then reboot, that will cure it.



Please make sure you include the combo fix log in your next reply as well as describe how your computer is running now

[hillan7]

my computer and most importantly my AVAST is running as it should. haven't come across any problems

[essexboy]

Subject to no further problems   

I will remove my tools now and give some recommendations, but, I would like you to run for 24 hours or so and come back if you have any problems 

Now the best part of the day ----- Your log now appears clean  :thumbsup:

A good workman always cleans up after himself so..The following will implement some cleanup procedures as well as reset  System Restore points:

Run OTL

• Under the Custom Scans/Fixes box at the bottom, paste in the following
  

  :Commands
  [resethosts]
  [emptytemp]
  [Reboot]

• Then click the Run Fix button at the top
  
• Let the program run unhindered, reboot the PC when it is done

Remove ComboFix

• Hold down the Windows key + R on your keyboard. This will display the Run dialogue box
  
• In the Run box, type in ComboFix /Uninstall (Notice the space between the "x" and "/") then click OK
  
  
  
  
• Follow the prompts on the screen
• A message should appear confirming that ComboFix was uninstalled

Run OTL and hit the cleanup button.  It will remove all the programmes we have used plus itself. 

We will now confirm that your hidden files are set to that, as some of the tools I use will change that

• Go to control panel
• Select folder options (Appearance > Folder options in category view)
• Select the View Tab.
• Under the Hidden files and folders heading select Do not show hidden files and folders.
  
• Click Yes to confirm.
• Click OK.

Your Java is out of date. Older versions have vulnerabilities that malware can use to infect your system.
Please follow these steps to remove older version of Java components and upgrade the application.

 Upgrading Java:

• Go to this site  and click Do I have Java
  
• It will check your current version and then offer to update to the latest version

SPRING CLEAN

To manually create a new Restore Point
 

• Go to Control Panel and select System
  
• Select System
  
• On the left select System Protection and accept the warning if you get one
  
• Select System Protection Tab
  
• Select Create at the bottom
  
• Type in a name i.e. Clean
• Select Create
  

Now we can purge the infected ones

• GoStart > All programs > Accessories > system tools
  
• Right click Disc cleanup and select run as administrator
  
• Select Your main drive and accept the warning if you get one
  
• For a few moments the system will make some calculations
• Select the More Options tab
  
• In the System Restore and Shadow Backups select Clean up
  
• Select Delete on the pop up
  
• Select OK
• Select Delete

Now that you are clean, to help protect your computer in the future I recommend that you get the following free programmes:

Malwarebytes.  Update and run weekly to keep your system clean

Download and install FileHippo update checker and run it monthly it will show you which programmes on your system need updating and give a download link

It is critical to have both a firewall and anti virus to protect your system and to keep them updated. To keep your operating system up to date visit

• Microsoft Windows Update

To learn more about how to protect yourself while on the internet read our little guide  How did I get infected in the first place ?

Keep safe  :wave:

[MasterVBGuru]

The problem is the July 2012 database update. 

I restored my Windows 7 (64-bit) Ultimate version from a June 2012 image I had created and it worked fine -- until Avast applied the July 2012 database.

I also tested this under Windows XP Professional (32-bit) SP3 in a Virtual Box.  It also was running the June 2012 database -- which works fine.  As soon as it updated the database to July 2012, I started to get MalWare error messages (see attachment).

The key is NOT to update Avast to the July 2012 database.  But I am not sure how I can roll back to the June 2012 database (which works fine).

[essexboy]

The data base is updated once or twice a day not including cloud updates...  So if it was a general false positive it would be cleared

Did you upload it from the virus chest as a false positive...

I see you have Avast 4.8 and not V7

But that has no bearing on the infection here

[MasterVBGuru]

     I uninstalled 4.8 from my laptop and installed V7.  Same problems persist.  Also:

    I restored an image of my Windows 7 Ultimate (x64) desktop (from an image I created back in June 2012) and all the problems went away -- until Avast updated the database to file version 120717-0.  Then the errors came back.

    I was also able to test this in a Windows XP Professional (SP3) virtual box which had the June 2012 database installed.  I turned automatic updates off to update the virus definition database, and everything worked fine.  When I updated the database to the July 2012 120717-0 database, the malware messages started appearing when I attempted to run my legitimate apps.

[essexboy]

Could you upload it from the virus chest as a false positive

Open Avast and go to the virus chest


Right click the file in the chest and select submit to virus labs


Once done manually update the virus definitions to send it

[MasterVBGuru]

I already submitted it earlier this morning (via the 4.8 version).

[MasterVBGuru]

Hello again.  I did some more testing to confirm it IS the July 17, 2012 version of the database:

-- Launched my Virtual Box with Windows XP (SP3) installed.  No other software is installed in this VirtualBox other than Avast (which is currently running the July 7, 2012 version of the database). 

-- Installed .NET Framework 3.5 SP1 and  Babel Obfuscator for .NET (version 3.5).

-- Scanned the program with Avast -- no errors.

-- Updated the Avast Antivirus database to the July 17, 2012 file version 120717-0.

-- Scanned the Babel.exe program -- Malware detected.

 

[MasterVBGuru]

I also installed and ran MalwareBytes 1.62 in my Windows XP VirtualBox before and after installing the Avast July 17, 2012 database update.  There were NO reports of Malware.

So here's how I fixed my machine:

--Made a copy of 400.vps (the July 7, 2012 version of the database) from my VirtualBox.
--Uninstalled Avast 4.8 Home from my desktop
--Rebooted the machine
--Installed Avast 4.8 Home on my desktop
--Before rebooting, I changed the program settings, changing BOTH the "Update" options (program/virus database) to MANUAL and copying the 400.vps database to the DATA folder.
--Rebooted machine
--Entered the license key.
--Clicked on the ABOUT menu option to confirm I am running the July 7, 2012 virus definition (file version 120705-0)
--Right-clicked on the program that was generating a "Malware" error (i.e. Babel.exe); no error message.  Application now runs flawlessly.

I will wait a month or so before updating the Avast Virus Definition Database until they have had a chance to fix this.  I suibmitted the application triggering the false positive (Babel Obfuscator for .NET 3.5.0).

[essexboy]

I think Avast is probably alerting to the fact that it obfuscates any .net assemblies.. This is a malware tactic.

So you will need to wait until they have confirmed the false positive I'm afraid

[DavidR]

Will you stop creating multiple topics and posts relating to the same issue, it just duplicates/triplicates the effort for those trying to help.
#
Please stick with this topic http://forum.avast.com/index.php?topic=101526.0 rather than hijack this one.