Date discovered:03/12/2009
In the wild:Yes
Reported Infections:Low
Distribution Potential:Low
Damage Potential:Low to medium
Static file:Yes
File size:108.514 Bytes
MD5 checksum:392c688556f4fb8f1254152bb4ed6900
IVDF version:

 General Method of propagation:
   • Autorun feature

   •  Symantec: Trojan.Packed.NsAnti
   •  Mcafee: W32/Autorun.worm.zzw
   •  Kaspersky: Worm.Win32.AutoRun.foc
   •  TrendMicro: WORM_AUTORUN.EMB
   •  F-Secure: Worm:W32/Agent.KAZ
   •  Sophos: Mal/Autorun-K
   •  Panda: W32/Autorun.ISH
   •  VirusBuster: Worm.AutoRun.NNX
   •  Eset: Win32/PSW.OnLineGames.NMY
   •  Bitdefender: Trojan.PWS.OnlineGames.KBWJ

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

Side effects:
   • Downloads malicious files
   • Drops malicious files
   • Lowers security settings
   • Registry modification

 Files It copies itself to the following locations:
   • %SYSDIR%\olhrwef.exe
   • %drive%\0xuc.com

It deletes the initially executed copy of itself.

The following files are created:

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

%SYSDIR%\drivers\klif.sys Further investigation pointed out that this file is malware, too. Detected as: RKIT/Agent.3584

%SYSDIR%\nmdfgds0.dll Further investigation pointed out that this file is malware, too. Detected as: TR/Crypt.ZPACK.Gen

It tries to download a file:

– The location is the following:
   • http://hjyuw2.com/xm**********
It is saved on the local hard drive under: %TEMPDIR%\help1[1].rar Furthermore this file gets executed after it was fully downloaded.

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

– [HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
   • "cdoosoft"="%SYSDIR%\olhrwef.exe"

The following registry keys are added:

   • "urlinfo"="%character string%"

– [HKLM\SYSTEM\ControlSet001\Services\KAVsys]
   • "Type"=dword:00000001
   • "ErrorControl"=dword:00000001
   • "Start"=dword:00000001
   • "ImagePath"="\??\%SYSDIR%\drivers\klif.sys"

The following registry keys are changed:

Various Explorer settings:

– [HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced]
   New value:
   • "Hidden"=dword:0x00000002
   • "ShowSuperHidden"=dword:0x00000000

– [HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced\
   New value:
   • "CheckedValue"=dword:0x00000000

 Injection –  It injects the following file into a process: %SYSDIR%\nmdfgds0.dll

    Process name:
   • explorer.exe

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

説明の挿入者 Alexandru Dinu の 2010年7月6日火曜日
説明の更新者 Alexandru Dinu の 2010年7月6日火曜日

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