W32/Yahlover.worm!EF8​FE87E6FE3

This page shows details and results of our analysis on the malware W32/Yahlover.worm!EF8FE87E6FE3

Overview

Viruses are self-replicating. They are often spread by a network or by transmission to a removable medium such as a removable disk, writable CD, or USB drive. Viruses may also spread by infecting files on a network file system or a file system that is shared by another computer.


Minimum DAT

7032 (2013-04-01)

Updated DAT

7032 (2013-04-01)

Minimum Engine

5400.1158

File Length

135680

Description Added

2013-04-02

Description Modified

2013-04-02

Malware Proliferation

Characteristics

This is a Virus

File PropertiesProperty Values
McAfee DetectionW32/YahLover.worm
Length135680 bytes
MD5ef8fe87e6fe349842460b80d0b16ee2b
SHA1b7c2b88d092029bc5894a37b5e0380e842241791


Other Common Detection Aliases

Company NamesDetection Names
ahnlabWin-Trojan/Xema.variant
avastWin32:Malware-gen
AVG (GriSoft)VB2.ABK
aviraTR/VB.EWS
KasperskyTrojan.Win32.Scar.hlgv
BitDefenderGen:Trojan.Heur.iyW@rXTgnTcib
clamavTrojan.VB-1623
Dr.WebTrojan.Opclose
F-ProtW32/Trojan2.MPL
MicrosoftWorm:Win32/SillyFDC.O
SymantecW32.SillyFDC
EsetWin32/VB.PTH trojan (variant)
normanObfuscated.H5!genr (trojan)
pandaTrj/Genetic.gen
risingWorm.Win32.VobfusEx.e
SophosMal/Behav-043
Trend MicroMal_OtorunN
vba32Worm.AutoRun.gog
V-BusterWorm.AutoRun!ECz76J6Hq7w
Vet (Computer Associates)Win32/fakeFLDR_i

Other brands and names may be claimed as the property of others.


ActivitiesRisk Levels
Modifies Windows explorer file browser's Advanced settings. Sometimes used by malware to make executable files look like documents.Medium
Attempts to launch an instance of the Windows file system explorer.Low
Enumerates many system files and directories.Low
Enumerates process listLow
Adds or modifies Internet Explorer cookiesLow
No digital signature is presentInformational


McAfee ScansScan Detections
McAfee BetaW32/YahLover.worm
McAfee SupportedW32/YahLover.worm



System Changes

Some path values have been replaced with environment variables as the exact location may vary with different configurations.
e.g.
%WINDIR% = \WINDOWS (Windows 9x/ME/XP/Vista/7), \WINNT (Windows NT/2000)
%PROGRAMFILES% = \Program Files


The following files were analyzed:

B7C2B88D092029BC5894A37B5E0380E842241791

The following files have been added to the system:

  • %WINDIR%\SYSTEM32\rundII32.exe
  • %WINDIR%\SYSTEM32\msng.exe
  • %WINDIR%\SYSTEM32\rundll32.exe

The following files were temporarily written to disk then later removed:

  • C:\~0002ftd.tmp

The following registry elements have been created:

  • HKEY_CURRENT_USER\SOFTWARE\VB AND VBA PROGRAM SETTINGS\
  • HKEY_CURRENT_USER\SOFTWARE\VB AND VBA PROGRAM SETTINGS\SVCHOST\
  • HKEY_CURRENT_USER\SOFTWARE\VB AND VBA PROGRAM SETTINGS\SVCHOST\OPEN\

The following registry elements have been changed:

  • HKEY_CURRENT_USER\SOFTWARE\MICROSOFT\INTERNET EXPLORER\TOOLBAR\LOCKED = 1
  • HKEY_CURRENT_USER\SOFTWARE\MICROSOFT\WINDOWS\CURRENTVERSION\EXPLORER\ADVANCED\HIDEFILEEXT = 49
  • HKEY_CURRENT_USER\SOFTWARE\VB AND VBA PROGRAM SETTINGS\SVCHOST\OPEN\TIMES = 49
  • HKEY_LOCAL_MACHINE\SOFTWARE\MICROSOFT\WINDOWS\CURRENTVERSION\RUN\MSNG = %WINDIR%\SYSTEM32\msng.exe

Symptoms

This symptoms of this detection are the files, registry, and network communication referenced in the characteristics section.

Method of Infection

Viruses are self-replicating. They are often spread by a network or by transmission to a removable medium such as a removable disk, writable CD, or USB drive. Viruses may also spread by infecting files on a network file system or a file system that is shared by another computer.

Removal

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.

Variants