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Virus Profile: ZeroAccess.en

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Virus Profile information details
Risk Assessment: Home Low | Corporate Low
Date Discovered: 6/13/2012
Date Added: 6/13/2012
Origin: N/A
Length: VARIES
Type: Trojan
Subtype: Win32
DAT Required: 6751
Removal Instructions
   
 
 
   

Description

This is a Trojan detection. Unlike viruses, trojans do not self-replicate. They are spread manually, often under the premise that they are beneficial or wanted. The most common installation methods involve system or security exploitation, and unsuspecting users manually executing unknown programs. Distribution channels include email, malicious or hacked web pages, Internet Relay Chat (IRC), peer-to-peer networks, etc.

Indication of Infection

Presence of above mentioned files and registry activities.

Methods of Infection

Trojans do not self-replicate. They are spread manually, often under the premise that the executable is something beneficial. Distribution channels include IRC, peer-to-peer networks, newsgroup postings, email spam, etc.
   

Virus Characteristics

Aliases:

  • Ikarus  - Trojan-Ransom.Win32.Birele
  • NOD32 - Win32/Sirefef.EV
  • Kaspersky - HEUR:Trojan.Win32.Generic 
  • Microsoft - Trojan:Win32/Sirefef.AB

Characteristics –

“ZeroAccess” is detection for this Trojan that uses an advanced rootkit to hide itself. It is often installed through drive-by-download attacks from malicious web sites.
 
“ZeroAccess.en” has the capabilities to remote access connection handling, perform Denial of Service (DoS) or Distributed DoS (DDoS), capture keyboard inputs, delete file or object, or terminate process.

The Trojan creates the following files into the below location

  • %windir%\assembly\GAC\Desktop.ini

And adds the following directories into the system

  • %windir%\assembly
  • %windir%\assembly\GAC
  • %windir%\assembly\GAC_MSIL

The following registry key has been added:

  • HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{36FC9E60-C465-11CF-8056-444553540000}\0007
  • HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4D36E967-E325-11CE-BFC1-08002BE10318}\0003
  • HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{71A27CDD-812A-11D0-BEC7-08002BE2092F}\0003
  • HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Eventlog\Application\SNL HiveManager
  • HKEY_USER\S-1-5-[varies]\Software\Microsoft\Windows\CurrentVersion\Controls Folder
  • HKEY_USER\S-1-5-[varies]\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{755b213c-be6c-11e1-9f83-000c29d7cda1}
  • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{29D3773E-54F4-23C2-D523-236A4453B845}_is1

The following registry values has been added

  • HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Eventlog\Application\SNL HiveManager\EventMessageFile: ""
  • HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Eventlog\Application\SNL HiveManager\TypesSupported: 0x00000007
  • HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Eventlog\Application\SNL HiveManager\CategoryMessageFile: ""
  • HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Eventlog\Application\SNL HiveManager\CategoryCount: 0x00000002
  • HKEY_USER\S-1-[varies]\Software\Microsoft\Internet Explorer\Toolbar\ShellBrowser\ITBarLayout: 11 00 00 00 4C 00 00 00 00 00 00 00 24 00 00 00 1B 00 00 00 52 00 00 00 01 00 00 00 20 07 00 00 A0 0F 00 00 05 00 00 00 62 05 00 00 26 00 00 00 02 00 00 00 21 07 00 00 A0 0F 00 00 04 00 00 00 21 01 00
  • HKEY_USER\S-1-[varies]\Software\Microsoft\Windows\CurrentVersion\Explorer\MountPoints2\{755b213c-be6c-11e1-9f83-000c29d7cda1}\BaseClass: "Drive"

And the below registry values has been modified to the system

  • HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Eventlog\Application\Sources: 'SNL HiveManager WSH WMIAdapter WmdmPmSp WinMgmt Winlogon Windows Product Activation Windows 3.1 Migration WebClient VSS vmtools VBRuntime Userinit Userenv UploadM Tlntsvr SysmonLog SpoolerCtrs Software Installation SclgNtfy SceSrv
    SceCli safrslv SAFrdms PerfProc PerfOS PerfNet Perfmon Perflib PerfDisk Perfctrs Offline Files Oakley ntbackup MsiInstaller MSDTC Client MSDTC mnmsrvc Microsoft H.323 Telephony Service Provider LoadPerf HelpSvc Folder Redirection File Deployment EventSystem ESENT EAPOL DrWatson DiskQuota crypt32 COM+ Ci Chkdsk AutoEnrollment Autochk Application Management Application Hang Application Error Application'
  • HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WinSock2\Parameters\NameSpace_Catalog5\Catalog_Entries\000000000001\
    LibraryPath = "%SystemRoot%\System32\mswsock.dll"
  • HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WinSock2\Parameters\NameSpace_Catalog5\Catalog_Entries\000000000001\
    LibraryPath = "mswsock.dll"
  • HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WinSock2\Parameters\NameSpace_Catalog5\Catalog_Entries\000000000003\
    LibraryPath = "%SystemRoot%\System32\mswsock.dll"
  • HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WinSock2\Parameters\NameSpace_Catalog5\Catalog_Entries\000000000003\
    LibraryPath ="mswsock.dll"
   

All Users:

Please use the following instructions for all supported versions of Windows to remove threats and other potential risks:

1.Disable System Restore .

2.Update to current engine and DAT files for detection and removal.

3.Run a complete system scan.

Modifications made to the system Registry and/or INI files for the purposes of hooking system startup, will be successfully removed if cleaning with the recommended engine and DAT combination (or higher).

1. Please go to the Microsoft Recovery Console and restore a clean MBR.

On windows XP:

Insert the Windows XP CD into the CD-ROM drive and restart the computer.
When the "Welcome to Setup" screen appears, press R to start the Recovery Console.
Select the Windows installation that is compromised and provide the administrator password
Issue 'fixmbr' command to restore the Master Boot Record
Follow onscreen instructions
Reset and remove the CD from CD-ROM drive.


On Windows Vista and 7:

Insert the Windows CD into the CD-ROM drive and restart the computer.
Click on "Repair Your Computer"
When the System Recovery Options dialog comes up, choose the Command Prompt.
Issue 'bootrec /fixmbr' command to restore the Master Boot Record
Follow onscreen instructions
Reset and remove the CD from CD-ROM drive.