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Date discovered:01/02/2010
In the wild:Yes
Reported Infections:Low to medium
Distribution Potential:Low to medium
Damage Potential:Low to medium
Static file:Yes
File size:823.665 Bytes
MD5 checksum:1dbefef6c17f82a4a4c90d7ea9476a6f
IVDF version:

 General Method of propagation:
   • Autorun feature

   •  Mcafee: W32/YahLover.worm
   •  Sophos: Mal/Generic-A
   •  Panda: W32/Autorun.JVM
   •  Eset: Win32/Sohanad.NFJ
   •  Bitdefender: Win32.Worm.Yahlover.N

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

Side effects:
   • Downloads a malicious file
   • Drops malicious files
   • Registry modification

 Files It copies itself to the following locations:
   • %drive%\%all directories%\%folder name%.exe
   • %drive%\SICHOST.exe
   • %drive%\New Folder.exe

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 download a file:

– The location is the following:

It tries to executes the following files:

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

– Filename:
   • AT /delete /yes

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

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

 Registry One of the following values is added in order to run the process after reboot:

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

The following registry key is added:

The following registry keys are changed:

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

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

– [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"=""

 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 Wednesday, April 7, 2010
Description updated by Andrei Ivanes on Thursday, April 8, 2010

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