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Date discovered:10/03/2011
In the wild:Yes
Reported Infections:Low to medium
Distribution Potential:Low to medium
Damage Potential:Low to medium
Static file:Yes
File size:754.672 Bytes
MD5 checksum:b9df337177cf691fc4a799e3bb15faaa
VDF version:
IVDF version:

 General Methods of propagation:
   • Autorun feature
   • Messenger

   •  Kaspersky: Worm.Win32.AutoRun.fnc
   •  F-Secure: Worm:W32/Autorun.NG
   •  Bitdefender: Trojan.Generic.KDV.185767
   •  GData: Trojan.Generic.KDV.185767
   •  DrWeb: Win32.HLLW.Autoruner.25412

Platforms / OS:
   • Windows 2000
   • Windows XP
   • Windows 2003

Side effects:
   • Drops malicious files
   • Registry modification

 Files It copies itself to the following locations:
   • %WINDIR%\system3_.exe
   • %SYSDIR%\system3_.exe
   • %all shared folders%\%folder name%.exe
   • %drive%\system3_.exe

It deletes the following files:
   • C:\System Volume Information\MountPointManagerRemoteDatabase
   • C:\System Volume Information\tracking.log

The following files are created:

%drive%\autorun.inf This is a non malicious text file with the following content:
   • %code that runs malware%

It tries to execute the following files:

– Filename:
   • %SYSDIR%\cmd.exe /C AT /delete /yes

– Filename:
   • %SYSDIR%\cmd.exe /C AT 09:00 /interactive /EVERY:m,t,w,th,f,s,su %SYSDIR%\system3_.exe

– Filename:
   • %SYSDIR%\cmd.exe /C cacls "C:\system volume information" /e /g "%current username%":f

 Registry The following registry key is added in order to run the process after reboot:

– [HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
   • "Yahoo Messengger"="%SYSDIR%\system3_.exe"

The following registry keys are added:

– [HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System]
   • "DisableRegistryTools"=dword:0x00000001
   • "DisableTaskMgr"=dword:0x00000001

– [HKLM\SYSTEM\CurrentControlSet\Services\Schedule]
   • "AtTaskMaxHours"=dword:0x00000000

– [HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer]
   • "NofolderOptions"=dword:0x00000001

– [HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\
   • "shared"="\New Folder.exe"

The following registry keys are changed:

– [HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon]
   New value:
   • "Shell"="Explorer.exe system3_.exe"

– [HKCU\Software\Microsoft\Internet Explorer\Main]
   New value:
   • "Start Page"=""

– [HKLM\SOFTWARE\Microsoft\Internet Explorer\MAIN]
   New value:
   • "Default_Page_URL"=""
   • "Default_Search_URL"=""
   • "Search Page"=""
   • "Start Page"=""

 Messenger It is spreading via Messenger. The characteristics are described below:

– Yahoo Messenger

The URL then refers to a copy of the described malware. If the user downloads and executes this file the infection process will start again.

 Miscellaneous Accesses internet resources:

 File details Runtime packer:
In order to aggravate detection and reduce size of the file it is packed with a runtime packer.

Description inserted by Petre Galan on Friday, June 17, 2011
Description updated by Petre Galan on Friday, June 17, 2011

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