Virus:Worm/VB.cqm.2
Date discovered:18/12/2008
Type:Worm
In the wild:Yes
Reported Infections:Low
Distribution Potential:Low to medium
Damage Potential:Medium
Static file:No
File size:~ 107.520 Bytes
IVDF version:7.01.00.251 - Thursday, December 18, 2008

 General Method of propagation:
   • Mapped network drives


Aliases:
   •  Symantec: W32.Imaut.U
   •  Kaspersky: Worm.Win32.VB.ck
   •  F-Secure: Worm.Win32.VB.ck
   •  Sophos: W32/Sohana-G
   •  Panda: W32/Sohanat.BV.worm
   •  Grisoft: Worm/VB.EIK
   •  VirusBuster: Worm.VB.EXY
   •  Eset: Win32/Sohanad.AI worm
   •  Bitdefender: Worm.IM.Sohanad.K

Similar detection:
   •  Worm/VB.cqm.1


Platforms / OS:
   • Windows 95
   • Windows 98
   • Windows 98 SE
   • Windows NT
   • Windows ME
   • Windows 2000
   • Windows XP
   • Windows 2003


Side effects:
   • Registry modification

 Files It copies itself to the following locations:
   • %drive%\New Folder.exe
   • %network shares%\New Folder.exe
   • %SYSDIR%\lsass.exe
   • %WINDIR%\lsass.exe



It deletes the following files:
   • %WINDIR%\pchealth\helpctr\binaries\msconfig.exe
   • %SYSDIR%\restore\rstrui.exe

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

– [HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon]
   • Userinit="userinit.exe,%SYSDIR%\lsass.exe"
   • shell="explorer.exe %SYSDIR%\lsass.exe"



The value of the following registry key is removed:

–  [HKLM\Software\Microsoft\Windows\CurrentVersion\Run]
   • BkavFw



The following registry keys are added:

– [HKCU\Software\Yahoo\pager\View\YMSGR_buzz]
   • content url="http://thecoolpics.net/"

– [HKLM\SOFTWARE\Policies\Microsoft\Windows NT\SystemRestore]
   • DisableConfig=dword:00000001



The following registry keys are changed:

Internet Explorer's start page:
– [HKCU\Software\Microsoft\Internet Explorer\Main]
   New value:
   • Start Page="http://thecoolpics.net/"

– [HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer]
   New value:
   • NoFolderOptions=dword:00000001
   • NoRun=dword:00000001

– [HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced]
   Old value:
   • Hidden=dword:00000001
   • HideFileExt=dword:00000000
   New value:
   • Hidden=dword:00000002
   • HideFileExt=dword:00000001

Disable Regedit and Task Manager:
– [HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System]
   New value:
   • "DisableRegistryTools"=dword:00000001
   • "DisableTaskMgr"=dword:00000001

 File details Programming language:
 The malware program was written in Visual Basic.


Runtime packer:
In order to aggravate detection and reduce size of the file it is packed with the following runtime packer:
   • UPX

Description inserted by Thomas Wegele on Wednesday, December 17, 2008
Description updated by Thomas Wegele on Thursday, December 18, 2008

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