Malicious URL blocked, svchost.exe - firewall inaccessible

[martinetti]

Hi,

I'm a assisting a friend who's got an infected system.

The problem was detected by Avast Free Antvirus background scan after updating the software (therefore it's not possible to determine the source or when the infection happened).

AV constantly reports a malicious URL being blocked. The file mentioned is svchost.exe.
In consequence of the infection the Windows firewall isn't accessible anymore.

(perhaps exactly the same as described in http://forum.avast.com/index.php?topic=102417.msg819957#msg819957)

According to  http://forum.avast.com/index.php?topic=53253.0 we did some scans and clean-ups (see logs attached), but the firewall stays inaccessible.

You're help would be much appreciated! :-)

Best regards,
Martinetti

[martinetti]

more log files

[mikaelrask]

hey and welcome to the forum. i will drop a note to one of our malware expert here on the forum on your topic.

[Pondus]

your malwarebytes log say "no action taken" ...... you need to click the "remove selected" button after scan

anyway it seems you have ZeroAccess rootkit that most likely need additional tools to be removed

[martinetti]

Thank you for your quick reply!

your malwarebytes log say "no action taken" ...... you need to click the "remove selected" button after scan

Yep. We deleted both files: one by one... ;-) We 'forgot' one which made a 2nd run necessary. The logs have been created before the deletions. The log file of the 3rd run reports no infections.

[essexboy]

Hi there lets give this a whirl, please attach all logs and once the runs are complete let me know if you are still getting the alerts 

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
  
  
  

Code: [Select]

:OTL
IE - HKU\S-1-5-21-839522115-362288127-725345543-1002\Software\Microsoft\Windows\CurrentVersion\Internet Settings: "ProxyOverride" = <local>;127.0.0.1:9421;
FF - prefs.js..extensions.enabledItems: {CAFEEFAC-0016-0000-0020-ABCDEFFEDCBA}:6.0.20
FF - prefs.js..extensions.enabledItems: {CAFEEFAC-0016-0000-0021-ABCDEFFEDCBA}:6.0.21
@Alternate Data Stream - 48 bytes -> C:\WINDOWS:FC55884293DF59E6

:Commands
[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 the latest version of TDSSKiller from here and save it to your Desktop.
 
 

• Doubleclick on TDSSKiller.exe to run the application
  
  
  
• Then click on Change parameters.
   
  
   
  
• Check the boxes beside Verify Driver Digital Signature and Detect TDLFS file system, then click OK.
   
  
• Click the Start Scan button.
   
   
  
• If a suspicious object is detected, the default action will be Skip, click on Continue.
   
  
   
  
• If malicious objects are found, they will show in the Scan results and offer three (3) options.
• Ensure Cure is selected, then click Continue => Reboot now to finish the cleaning process.
  
  
• Get the report by selecting Reports

 

• Note: If Cure is not available, please choose Skip instead, do not choose Delete unless instructed.
  

Please copy and paste its contents on your next reply.

FINALLY

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

[martinetti]

Hi Essexboy,

thank you for your answer.

We've started the customized OTL Fix 90 minutes ago. Soon after starting the program the system froze (ctrl+alt+del does not open task manager).

Now I wonder if this is a usual behaviour? Shall we go on waiting? What would you recommend to do?

[essexboy]

OK that is probably MBAM blocking OTL from running.  Stop OTL and proceed to the remainder of the fix please
We will pick up on that later

[martinetti]

Well, even with MBAM and AV turned off, OTL made the system freeze...

After a restart TDSSKiller run without any problems.
Several suspicious objects were found, but no malicious objects.

ComboFix could not connect to the internet, thus the Windows Recovery Console wasn't installed.

Nevertheless everything seems fine at the moment: there are no more AV messages popping up and we regained control of the firewall! :-)

Thank you so much!!!

Are there any further steps necessary to ensure the cleanliness of the system?

[essexboy]

As soon as you are happy let me know and I will remove my rubbish