Virus:BDS/VB.avf
Date discovered:29/08/2006
Type:Backdoor Server
In the wild:No
Reported Infections:Low
Distribution Potential:Low
Damage Potential:Medium
Static file:Yes
File size:48.188 Bytes
MD5 checksum:eecffebb81611d60d3c82748ac84433a
VDF version:6.35.00.107
IVDF version:6.35.00.133 - Friday, July 7, 2006

 General Method of propagation:
   • No own spreading routine


Aliases:
   •  Symantec: Infostealer.Lemir
   •  Kaspersky: Backdoor.Win32.VB.avf
   •  TrendMicro: BKDR_VB.SE
   •  VirusBuster: Backdoor.VB.WOM
   •  Bitdefender: Backdoor.VB.ARA


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


Side effects:
   • Drops files
   • Registry modification
   • Steals information
   • Third party control

 Files It copies itself to the following locations:
   • %WINDIR%\SMSS.EXE
   • %SYSDIR%\rundll32.com
   • %SYSDIR%\finder.com
   • %SYSDIR%\MSCONFIG.COM
   • %SYSDIR%\dxdiag.com
   • %SYSDIR%\regedit.com
   • %WINDIR%\finder.com
   • %WINDIR%\explorer.com
   • %WINDIR%\1.com
   • %WINDIR%\ExERoute.exe
   • %PROGRAM FILES%\Internet Explorer\iexplore.com
   • %SYSDIR%\command.pif
   • %PROGRAM FILES%\Common Files\iexplore.pif
   • D:\pagefile.pif



The following files are created:

– %WINDIR%\BOOT.BIN.BAK
– D:\autorun.inf

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

– [HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
   • "TProgram"="%WINDIR%\SMSS.EXE"



The following registry keys are added:

– [HKCR\winfiles\DefaultIcon]
   • "(Default)"="%1"

– [HKCR\winfiles\Shell\Open\Command]
   • "(Default)"="%WINDIR%\ExERoute.exe "%1" %*"



The following registry keys are changed:

– [HKCR\.lnk\ShellNew]
   New value:
   • "command"="rundll32.com appwiz.cpl,NewLinkHere %1"

– [HKCU\Software\Microsoft\Internet Explorer\Main]
   New value:
   • "Check_Associations"="No"

– [HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon]
   New value:
   • "Shell"="Explorer.exe 1"

– [HKCR\.bfc\ShellNew]
   New value:
   • "command"="%SystemRoot%\system32\rundll32.com %SystemRoot%\system32syncui.dll,Briefcase_Create %2!d! %1"

– [HKCR\cplfile\shell\cplopen\command]
   New value:
   • "(Default)"="rundll32.com shell32.dll,Control_RunDLL %1,%*"

– [HKCR\dunfile\shell\open\command]
   New value:
   • "(Default)"="%SystemRoot%\system32\rundll32.com NETSHELL.DLL,InvokeDunFile %1"

– [HKCR\htmlfile\shell\Print\command]
   New value:
   • "(Default)"=""%PROGRAM FILES%\Microsoft Office\Office10\msohtmed.exe" /p %1"

– [HKCR\inffile\shell\Install\command]
   New value:
   • "(Default)"="%SystemRoot%\System32\rundll32.com setupapi,InstallHinfSection DefaultInstall 132 %1"

– [HKCR\InternetShortcut\shell\open\command]
   New value:
   • "(Default)"="finder.com shdocvw.dll,OpenURL %l"

– [HKCR\scrfile\shell\install\command]
   New value:
   • "(Default)"="finder.com desk.cpl,InstallScreenSaver %l"

– [HKCR\scriptletfile\Shell\Generate Typelib\command]
   New value:
   • "(Default)"=""%SYSDIR%\finder.com" %WINDIR%\System32scrobj.dll,GenerateTypeLib "%1""

– [HKCR\telnet\shell\open\command]
   New value:
   • "(Default)"="finder.com url.dll,TelnetProtocolHandler %l"

– [HKCR\Unknown\shell\openas\command]
   New value:
   • "(Default)"="%SystemRoot%\system32\finder.com %SystemRoot%\system32\shell32.dll,OpenAs_RunDLL %1"

– [HKCR\htmlfile\shell\open\command]
   New value:
   • "(Default)"=""%PROGRAM FILES%\Internet Explorer\iexplore.com" -nohome"

– [HKCR\Applications\iexplore.exe\shell\open\command]
   New value:
   • "(Default)"=""%PROGRAM FILES%\Internet Explorer\iexplore.com" %1"

– [HKCR\CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\shell\
   OpenHomePage\Command]
   New value:
   • "(Default)"=""%PROGRAM FILES%\Internet Explorer\iexplore.com""

– [HKCR\ftp\shell\open\command]
   New value:
   • "(Default)"=""%PROGRAM FILES%\Internet Explorer\iexplore.com" %1"

– [HKCR\htmlfile\shell\opennew\command]
   New value:
   • "(Default)"=""%PROGRAM FILES%\Common Files\iexplore.pif" %1"

– [HKCR\http\shell\open\command]
   New value:
   • "(Default)"=""%PROGRAM FILES%\Common Files\iexplore.pif" -nohome"

– [HKCR\Drive\shell\find\command]
   New value:
   • "(Default)"="%SystemRoot%\explorer.com"

– [HKCR\.exe]
   New value:
   • "(Default)"="winfiles"

 Process termination List of processes that are terminated:
   • CCENTER%random character string%; ASSISTSE%random character
      string%; KPFW%random character string%; AGENTSVR%random
      character string%; KV%random character string%;
      KREG%random character string%; IEFIND%random character
      string%; IPARMOR%random character string%; SVI.EXE;
      UPHC%random character string%; RULEWIZE%random character
      string%; FYGT%random character string%; RFWSRV%random
      character string%; RFWMA%random character string%


 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 a runtime packer.

Description inserted by Monica Ghitun on Tuesday, August 29, 2006
Description updated by Monica Ghitun on Friday, November 24, 2006

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