Help !!! Trojan Backdoor Bifrost

Le PC de mon fils (sur Vista) a "chopé" ce virus, on lui a pris les données de son compte Dofus... Il faut que je me débarasse de ce machin mais je n'y parviens pas toute seule. J'ai fait des tas de scan Defenza, Spybot SD, Spy Sweeper : ce dernier a "trouvé" le virus mais il faut que j'achète le programme pour m'en débarrasser !!!
Le pc a un antivirus avast familial qui n'a rien trouvé !

J'ai téléchargé Hijackthis et fait un scan. Voici le rapport ci-dessous, auquel je ne comprends rien... Que dois je faire maintenant ?

Merci de votre aide...

Rapport Hijackthis :

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 11:55:12, on 20/08/2008
Platform: Windows Vista (WinNT 6.00.1904)
MSIE: Internet Explorer v7.00 (7.00.6000.16711)
Boot mode: Normal

Running processes:
C:\Windows\system32\Dwm.exe
C:\Windows\Explorer.EXE
C:\Windows\system32\taskeng.exe
C:\Program Files\Windows Defender\MSASCui.exe
C:\Program Files\Camera Assistant Software for Toshiba\traybar.exe
C:\Program Files\TOSHIBA\Power Saver\TPwrMain.exe
C:\Program Files\TOSHIBA\SmoothView\SmoothView.exe
C:\Program Files\TOSHIBA\FlashCards\TCrdMain.exe
C:\Program Files\Camera Assistant Software for Toshiba\CEC_MAIN.exe
C:\Program Files\Webroot\Spy Sweeper\SpySweeperUI.exe
C:\Program Files\TOSHIBA\Utilities\KeNotify.exe
C:\Program Files\TOSHIBA\ConfigFree\NDSTray.exe
C:\Program Files\IDM\Desktop SMS\DesktopSMS.exe
C:\Program Files\TOSHIBA\ConfigFree\CFSwMgr.exe
C:\Windows\RtHDVCpl.exe
C:\Program Files\ATI Technologies\ATI.ACE\Core-Static\MOM.EXE
C:\Program Files\Synaptics\SynTP\SynTPEnh.exe
C:\Program Files\TOSHIBA\Registration\ToshibaRegistration.exe
C:\Program Files\Microsoft Xbox 360 Accessories\XBoxStat.exe
C:\Program Files\Alwil Software\Avast4\ashDisp.exe
C:\Program Files\Windows Sidebar\sidebar.exe
C:\Program Files\Synaptics\SynTP\SynToshiba.exe
C:\Program Files\TOSHIBA\TOSCDSPD\TOSCDSPD.exe
C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
C:\Program Files\ATI Technologies\ATI.ACE\Core-Static\CCC.exe
C:\Program Files\Windows Mail\WinMail.exe
C:\Windows\system32\conime.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\Program Files\Internet Explorer\IEUser.exe
C:\Program Files\Common Files\Microsoft Shared\Windows Live\WLLoginProxy.exe
C:\Windows\system32\taskeng.exe
C:\Windows\system32\wuauclt.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\Windows\system32\Macromed\Flash\FlashUtil9f.exe
C:\Windows\system32\SearchFilterHost.exe
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=54896
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://google.fr/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://go.microsoft.com/fwlink/?LinkId=69157
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = http://go.microsoft.com/fwlink/?LinkId=54896
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=54896
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = http://go.microsoft.com/fwlink/?LinkId=69157
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant =
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,CustomizeSearch =
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName =
O1 - Hosts: ::1 localhost
O2 - BHO: Aide pour le lien d'Adobe PDF Reader - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Common Files\Adobe\Acrobat\ActiveX\AcroIEHelper.dll
O2 - BHO: Spybot-S&D IE Protection - {53707962-6F74-2D53-2644-206D7942484F} - C:\Program Files\Spybot - Search & Destroy\SDHelper.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.6.0\bin\ssv.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O2 - BHO: Programme d'aide de l'Assistant de connexion Windows Live - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Program Files\Common Files\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O4 - HKLM\..\Run: [Windows Defender] "C:\Program Files\Windows Defender\MSASCui.exe" -hide
O4 - HKLM\..\Run: [00TCrdMain] "C:\Program Files\TOSHIBA\FlashCards\TCrdMain.exe"
O4 - HKLM\..\Run: [KeNotify] "C:\Program Files\TOSHIBA\Utilities\KeNotify.exe"
O4 - HKLM\..\Run: [SVPWUTIL] "C:\Program Files\TOSHIBA\Utilities\SVPWUTIL.exe" SVPwUTIL
O4 - HKLM\..\Run: [NDSTray.exe] NDSTray.exe
O4 - HKLM\..\Run: [Desktop SMS] "C:\Program Files\IDM\Desktop SMS\DesktopSMS.exe" /auto
O4 - HKLM\..\Run: [RtHDVCpl] "C:\Windows\RtHDVCpl.exe"
O4 - HKLM\..\Run: [StartCCC] "C:\Program Files\ATI Technologies\ATI.ACE\Core-Static\CLIStart.exe"
O4 - HKLM\..\Run: [SynTPEnh] "C:\Program Files\Synaptics\SynTP\SynTPEnh.exe"
O4 - HKLM\..\Run: [Toshiba Registration] "C:\Program Files\Toshiba\Registration\ToshibaRegistration.exe"
O4 - HKLM\..\Run: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [SpySweeper] C:\Program Files\Webroot\Spy Sweeper\SpySweeperUI.exe /startintray
O4 - HKLM\..\Run: [SmoothView] "C:\Program Files\Toshiba\SmoothView\SmoothView.exe"
O4 - HKLM\..\Run: [TPwrMain] "C:\Program Files\TOSHIBA\Power Saver\TPwrMain.EXE"
O4 - HKLM\..\Run: [HSON] "C:\Program Files\TOSHIBA\TBS\HSON.exe"
O4 - HKCU\..\Run: [Sidebar] "C:\Program Files\Windows Sidebar\sidebar.exe" /autoRun
O4 - HKCU\..\Run: [WindowsWelcomeCenter] "C:\Windows\system32\rundll32.exe" oobefldr.dll,ShowWelcomeCenter
O4 - HKCU\..\Run: [TOSCDSPD] "C:\Program Files\TOSHIBA\TOSCDSPD\TOSCDSPD.exe"
O4 - HKCU\..\Run: [SpybotSD TeaTimer] "C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe"
O4 - HKUS\S-1-5-19\..\Run: [Sidebar] %ProgramFiles%\Windows Sidebar\Sidebar.exe /detectMem (User 'SERVICE LOCAL')
O4 - HKUS\S-1-5-19\..\Run: [WindowsWelcomeCenter] rundll32.exe oobefldr.dll,ShowWelcomeCenter (User 'SERVICE LOCAL')
O4 - HKUS\S-1-5-20\..\Run: [Sidebar] %ProgramFiles%\Windows Sidebar\Sidebar.exe /detectMem (User 'SERVICE RÉSEAU')
O4 - Global Startup: Microsoft Office.lnk = C:\Program Files\Microsoft Office\Office\OSA9.EXE
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0\bin\npjpi160.dll
O9 - Extra 'Tools' menuitem: Console Java (Sun) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0\bin\npjpi160.dll
O9 - Extra button: eBay - Achetez, Vendez - {76577871-04EC-495E-A12B-91F7C3600AFA} - http://rover.ebay.com/rover/1/709-44555-9400-3/4 (file missing)
O9 - Extra button: Amazon.fr - {8A918C1D-E123-4E36-B562-5C1519E434CE} - http://www.amazon.fr/exec/obidos/r [...] &site=home (file missing)
O9 - Extra button: (no name) - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\Program Files\Spybot - Search & Destroy\SDHelper.dll
O9 - Extra 'Tools' menuitem: Spybot - Search && Destroy Configuration - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\Program Files\Spybot - Search & Destroy\SDHelper.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\wpclsp.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\wpclsp.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\wpclsp.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\wpclsp.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\wpclsp.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\wpclsp.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\wpclsp.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\wpclsp.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\wpclsp.dll
O13 - Gopher Prefix:
O16 - DPF: {D27CDB6E-AE6D-11CF-96B8-444553540000} (Shockwave Flash Object) - http://fpdownload2.macromedia.com/ [...] wflash.cab
O23 - Service: Agere Modem Call Progress Audio (AgereModemAudio) - Agere Systems - C:\Windows\system32\agrsmsvc.exe
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - ALWIL Software - C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: Ati External Event Utility - ATI Technologies Inc. - C:\Windows\system32\Ati2evxx.exe
O23 - Service: avast! Antivirus - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashServ.exe
O23 - Service: avast! Mail Scanner - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
O23 - Service: avast! Web Scanner - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
O23 - Service: ConfigFree Service (CFSvcs) - TOSHIBA CORPORATION - C:\Program Files\TOSHIBA\ConfigFree\CFSvcs.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Common Files\InstallShield\Driver\1050\Intel 32\IDriverT.exe
O23 - Service: TOSHIBA Navi Support Service (TNaviSrv) - TOSHIBA Corporation - C:\Program Files\TOSHIBA\TOSHIBA DVD PLAYER\TNaviSrv.exe
O23 - Service: TOSHIBA Optical Disc Drive Service (TODDSrv) - TOSHIBA Corporation - C:\Windows\system32\TODDSrv.exe
O23 - Service: TOSHIBA Power Saver (TosCoSrv) - TOSHIBA Corporation - C:\Program Files\TOSHIBA\Power Saver\TosCoSrv.exe
O23 - Service: TOSHIBA Bluetooth Service - Unknown owner - c:\Program Files\Toshiba\Bluetooth Toshiba Stack\TosBtSrv.exe (file missing)
O23 - Service: Ulead Burning Helper (UleadBurningHelper) - Ulead Systems, Inc. - C:\Program Files\Common Files\Ulead Systems\DVD\ULCDRSvr.exe
O23 - Service: Moteur Webroot Spy Sweeper (WebrootSpySweeperService) - Webroot Software, Inc. (www.webroot.com) - C:\Program Files\Webroot\Spy Sweeper\SpySweeper.exe

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