Scusate l'urgente. Mi e' apparso all'improvviso sul desktop un avviso di AVG,e' stato trovato un virus,ho cliccato -sposta in quarantena-.....e' apparso un altro avviso che diceva che cosi facendo il sisema si poteva arrestare......e infatti dopo un po' il computer si e' riavviato da solo........che devo fare con sto' virus?

Rifai una scansione con AVG in Modalità provvisoria, e vedi cosa rileva.
Poi scarica ed installa MalwareBytes:
clicca qui per il download : http://www.malwarebytes.org/
esegui una scansione completa del sistema e, una volta terminata la scansione,posta il log che verrà rilasciato in questa discussione.
Prima di fare la scansione AGGIORNALO.
Probabilmente (spero di sbagliarmi) è una variante del virus Vundo.
Poi posta un log di hijackthis

Si, MBAM In modalità normale.

NON pare affatto, stavolta, si tratti di un falso-positivo... è un malware per davvero.
http://www.incodesolutions.com/threats2/System32Rootupdatenfdll.php
http://www.oral8.cn/viruscom/viruscom_39328.html

Questo e' il log di Hijack this.



Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 18.52.22, on 19/12/2008
Platform: Windows XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP3 (6.00.2900.5512)
Boot mode: Normal

Running processes:
C:\WINDOWS\System32\smss.exe
C:\WINDOWS\system32\winlogon.exe
C:\WINDOWS\system32\services.exe
C:\WINDOWS\system32\lsass.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\ZoneLabs\vsmon.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\system32\spoolsv.exe
C:\Programmi\File comuni\Acronis\Schedule2\schedul2.exe
C:\Programmi\File comuni\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
C:\PROGRA~1\AVG\AVG8\avgwdsvc.exe
C:\Programmi\McAfee\SiteAdvisor\McSACore.exe
C:\Programmi\File comuni\Microsoft Shared\VS7DEBUG\MDM.EXE
C:\WINDOWS\system32\nvsvc32.exe
C:\WINDOWS\system32\HPZipm12.exe
C:\WINDOWS\system32\svchost.exe
C:\Programmi\File comuni\Acronis\Fomatik\TrueImageTryStartService.exe
C:\PROGRA~1\AVG\AVG8\avgam.exe
C:\PROGRA~1\AVG\AVG8\avgrsx.exe
C:\PROGRA~1\AVG\AVG8\avgnsx.exe
C:\Programmi\BillP Studios\WinPatrol\winpatrol.exe
C:\Programmi\Zone Labs\ZoneAlarm\zlclient.exe
C:\Programmi\IObit\IObit SmartDefrag\IObit SmartDefrag.exe
C:\PROGRA~1\AVG\AVG8\avgtray.exe
C:\PROGRA~1\AVG\AVG8\avgemc.exe
C:\WINDOWS\system32\wbem\wmiapsrv.exe
C:\Programmi\H3G\3G HSDPA Wireless Modem MD-@\WirelessCard.exe
C:\Programmi\Opera\Opera.exe
C:\Programmi\File comuni\Microsoft Shared\MODI\11.0\MSPVIEW.EXE
C:\WINDOWS\system32\WISPTIS.EXE
C:\Documents and Settings\User\Documenti\HIJACK THIS-spiware+\HijackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = http://www.yahoo.com/search/ie.html
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Local Page =
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Collegamenti
O2 - BHO: Supporto di collegamento per Adobe PDF Reader - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Programmi\File comuni\Adobe\Acrobat\ActiveX\AcroIEHelper.dll
O2 - BHO: WormRadar.com IESiteBlocker.NavFilter - {3CA2F312-6F6E-4B53-A66E-4E65E497C8C0} - C:\Programmi\AVG\AVG8\avgssie.dll
O2 - BHO: Spybot-S&D IE Protection - {53707962-6F74-2D53-2644-206D7942484F} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Programmi\Java\jre1.6.0_07\bin\ssv.dll
O2 - BHO: AVG Security Toolbar - {A057A204-BACC-4D26-9990-79A187E2698E} - C:\Programmi\AVG\AVG8\avgtoolbar.dll
O3 - Toolbar: AVG Security Toolbar - {A057A204-BACC-4D26-9990-79A187E2698E} - C:\Programmi\AVG\AVG8\avgtoolbar.dll
O4 - HKLM\..\Run: [WinPatrol] C:\Programmi\BillP Studios\WinPatrol\winpatrol.exe
O4 - HKLM\..\Run: [ZoneAlarm Client] "C:\Programmi\Zone Labs\ZoneAlarm\zlclient.exe"
O4 - HKLM\..\Run: [SmartDefrag] "C:\Programmi\IObit\IObit SmartDefrag\IObit SmartDefrag.exe" /StartUp
O4 - HKLM\..\Run: [AVG8_TRAY] C:\PROGRA~1\AVG\AVG8\avgtray.exe
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\system32\NvCpl.dll,NvStartup
O4 - HKCU\..\Run: [ccleaner] "C:\Programmi\CCleaner\CCleaner.exe" /AUTO
O8 - Extra context menu item: E&sporta in Microsoft Excel - res://C:\PROGRA~1\MICROS~2\OFFICE11\EXCEL.EXE/3000
O8 - Extra context menu item: Scarica con Download &Express - C:\Programmi\Download Express\Add_Url.htm
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Programmi\Java\jre1.6.0_07\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Programmi\Java\jre1.6.0_07\bin\ssv.dll
O9 - Extra button: Ricerche - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\OFFICE11\REFIEBAR.DLL
O9 - Extra button: (no name) - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O9 - Extra 'Tools' menuitem: Spybot - Search & Destroy Configuration - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O9 - Extra button: (no name) - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra 'Tools' menuitem: @xpsp3res.dll,-20001 - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Programmi\Messenger\msmsgs.exe
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Programmi\Messenger\msmsgs.exe
O16 - DPF: {8AD9C840-044E-11D1-B3E9-00805F499D93} (Java Runtime Environment 1.6.0) - http://javadl.sun.com/webapps/download/AutoDL?BundleId=23100
O17 - HKLM\System\CCS\Services\Tcpip\..\{AF77AF2B-BE5E-4FFE-B066-0C5D48C30B3F}: NameServer = 62.13.171.5 62.13.171.4
O18 - Protocol: linkscanner - {F274614C-63F8-47D5-A4D1-FBDDE494F8D1} - C:\Programmi\AVG\AVG8\avgpp.dll
O20 - AppInit_DLLs: avgrsstx.dll
O20 - Winlogon Notify: UpdateNf - updatenf.dll (file missing)
O23 - Service: Acronis Scheduler2 Service (AcrSch2Svc) - Acronis - C:\Programmi\File comuni\Acronis\Schedule2\schedul2.exe
O23 - Service: Apple Mobile Device - Apple, Inc. - C:\Programmi\File comuni\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
O23 - Service: AVG8 E-mail Scanner (avg8emc) - AVG Technologies CZ, s.r.o. - C:\PROGRA~1\AVG\AVG8\avgemc.exe
O23 - Service: AVG8 WatchDog (avg8wd) - AVG Technologies CZ, s.r.o. - C:\PROGRA~1\AVG\AVG8\avgwdsvc.exe
O23 - Service: Servizio iPod (iPod Service) - Apple Inc. - C:\Programmi\iPod\bin\iPodService.exe
O23 - Service: McAfee SiteAdvisor Service - Unknown owner - C:\Programmi\McAfee\SiteAdvisor\McSACore.exe
O23 - Service: NBService - Nero AG - C:\Programmi\Nero\Nero 7\Nero BackItUp\NBService.exe
O23 - Service: NMIndexingService - Nero AG - C:\Programmi\File comuni\Ahead\Lib\NMIndexingService.exe
O23 - Service: NVIDIA Display Driver Service (NVSvc) - NVIDIA Corporation - C:\WINDOWS\system32\nvsvc32.exe
O23 - Service: Pml Driver HPZ12 - HP - C:\WINDOWS\system32\HPZipm12.exe
O23 - Service: Acronis Try And Decide Service (TryAndDecideService) - Unknown owner - C:\Programmi\File comuni\Acronis\Fomatik\TrueImageTryStartService.exe
O23 - Service: TrueVector Internet Monitor (vsmon) - Zone Labs, LLC - C:\WINDOWS\system32\ZoneLabs\vsmon.exe

--
End of file - 6236 bytes

Attendi l'opinione di r16. A me, par che la riga da fixare (ma dubito ciò basti), sia la seguente:

O20 - Winlogon Notify: UpdateNf - updatenf.dll (file missing)

Il file, probabilmente, è "missing" perché l'ha "messo in prigione" AVG.
Inoltre, se fossi in te, eliminerei completamente il McAfee Site Advisor ("si picchia" con una delle funzioni di AVG [e questo vale identico per la versione free come per quella Professional]).
Infine, guarda che anche il tuo Java Runtime NON mi sembra aggiornato...

Anche a te ecofive.

Ecco il log di Hijack this.
r16...volevo chiederti: I due virus in quarantena di AVG li posso eliminare vero?



Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 5.29.58, on 20/12/2008
Platform: Windows XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP3 (6.00.2900.5512)
Boot mode: Normal

Running processes:
C:\WINDOWS\System32\smss.exe
C:\WINDOWS\system32\winlogon.exe
C:\WINDOWS\system32\services.exe
C:\WINDOWS\system32\lsass.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\ZoneLabs\vsmon.exe
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\system32\spoolsv.exe
C:\Programmi\File comuni\Acronis\Schedule2\schedul2.exe
C:\Programmi\File comuni\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
C:\PROGRA~1\AVG\AVG8\avgwdsvc.exe
C:\Programmi\Java\jre6\bin\jqs.exe
C:\Programmi\File comuni\Microsoft Shared\VS7DEBUG\MDM.EXE
C:\WINDOWS\system32\nvsvc32.exe
C:\WINDOWS\system32\HPZipm12.exe
C:\WINDOWS\system32\svchost.exe
C:\Programmi\File comuni\Acronis\Fomatik\TrueImageTryStartService.exe
C:\PROGRA~1\AVG\AVG8\avgam.exe
C:\PROGRA~1\AVG\AVG8\avgrsx.exe
C:\PROGRA~1\AVG\AVG8\avgnsx.exe
C:\Programmi\BillP Studios\WinPatrol\winpatrol.exe
C:\Programmi\Zone Labs\ZoneAlarm\zlclient.exe
C:\Programmi\IObit\IObit SmartDefrag\IObit SmartDefrag.exe
C:\PROGRA~1\AVG\AVG8\avgtray.exe
C:\Programmi\Java\jre6\bin\jusched.exe
C:\PROGRA~1\AVG\AVG8\avgemc.exe
C:\WINDOWS\system32\wbem\wmiapsrv.exe
C:\Programmi\H3G\3G HSDPA Wireless Modem MD-@\WirelessCard.exe
C:\Programmi\LimeWire\LimeWire.exe
C:\Programmi\Opera\Opera.exe
C:\Documents and Settings\User\Documenti\programmi franco\HIJACK THIS-spiware+\HijackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = http://www.yahoo.com/search/ie.html
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Local Page =
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings,ProxyOverride = *.local
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Collegamenti
O2 - BHO: Supporto di collegamento per Adobe PDF Reader - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Programmi\File comuni\Adobe\Acrobat\ActiveX\AcroIEHelper.dll
O2 - BHO: WormRadar.com IESiteBlocker.NavFilter - {3CA2F312-6F6E-4B53-A66E-4E65E497C8C0} - C:\Programmi\AVG\AVG8\avgssie.dll
O2 - BHO: Spybot-S&D IE Protection - {53707962-6F74-2D53-2644-206D7942484F} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O2 - BHO: Java(tm) Plug-In SSV Helper - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Programmi\Java\jre6\bin\ssv.dll
O2 - BHO: AVG Security Toolbar - {A057A204-BACC-4D26-9990-79A187E2698E} - C:\Programmi\AVG\AVG8\avgtoolbar.dll
O2 - BHO: Java(tm) Plug-In 2 SSV Helper - {DBC80044-A445-435b-BC74-9C25C1C588A9} - C:\Programmi\Java\jre6\bin\jp2ssv.dll
O2 - BHO: JQSIEStartDetectorImpl - {E7E6F031-17CE-4C07-BC86-EABFE594F69C} - C:\Programmi\Java\jre6\lib\deploy\jqs\ie\jqs_plugin.dll
O3 - Toolbar: AVG Security Toolbar - {A057A204-BACC-4D26-9990-79A187E2698E} - C:\Programmi\AVG\AVG8\avgtoolbar.dll
O4 - HKLM\..\Run: [WinPatrol] C:\Programmi\BillP Studios\WinPatrol\winpatrol.exe
O4 - HKLM\..\Run: [ZoneAlarm Client] "C:\Programmi\Zone Labs\ZoneAlarm\zlclient.exe"
O4 - HKLM\..\Run: [SmartDefrag] "C:\Programmi\IObit\IObit SmartDefrag\IObit SmartDefrag.exe" /StartUp
O4 - HKLM\..\Run: [AVG8_TRAY] C:\PROGRA~1\AVG\AVG8\avgtray.exe
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\system32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Programmi\Java\jre6\bin\jusched.exe"
O4 - HKCU\..\Run: [ccleaner] "C:\Programmi\CCleaner\CCleaner.exe" /AUTO
O8 - Extra context menu item: E&sporta in Microsoft Excel - res://C:\PROGRA~1\MICROS~2\OFFICE11\EXCEL.EXE/3000
O8 - Extra context menu item: Scarica con Download &Express - C:\Programmi\Download Express\Add_Url.htm
O9 - Extra button: Ricerche - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\OFFICE11\REFIEBAR.DLL
O9 - Extra button: (no name) - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O9 - Extra 'Tools' menuitem: Spybot - Search & Destroy Configuration - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O9 - Extra button: (no name) - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra 'Tools' menuitem: @xpsp3res.dll,-20001 - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Programmi\Messenger\msmsgs.exe
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Programmi\Messenger\msmsgs.exe
O17 - HKLM\System\CCS\Services\Tcpip\..\{AF77AF2B-BE5E-4FFE-B066-0C5D48C30B3F}: NameServer = 62.13.171.5 62.13.171.4
O18 - Protocol: linkscanner - {F274614C-63F8-47D5-A4D1-FBDDE494F8D1} - C:\Programmi\AVG\AVG8\avgpp.dll
O20 - AppInit_DLLs: avgrsstx.dll
O23 - Service: Acronis Scheduler2 Service (AcrSch2Svc) - Acronis - C:\Programmi\File comuni\Acronis\Schedule2\schedul2.exe
O23 - Service: Apple Mobile Device - Apple, Inc. - C:\Programmi\File comuni\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
O23 - Service: AVG8 E-mail Scanner (avg8emc) - AVG Technologies CZ, s.r.o. - C:\PROGRA~1\AVG\AVG8\avgemc.exe
O23 - Service: AVG8 WatchDog (avg8wd) - AVG Technologies CZ, s.r.o. - C:\PROGRA~1\AVG\AVG8\avgwdsvc.exe
O23 - Service: Servizio iPod (iPod Service) - Apple Inc. - C:\Programmi\iPod\bin\iPodService.exe
O23 - Service: Java Quick Starter (JavaQuickStarterService) - Sun Microsystems, Inc. - C:\Programmi\Java\jre6\bin\jqs.exe
O23 - Service: NBService - Nero AG - C:\Programmi\Nero\Nero 7\Nero BackItUp\NBService.exe
O23 - Service: NMIndexingService - Nero AG - C:\Programmi\File comuni\Ahead\Lib\NMIndexingService.exe
O23 - Service: NVIDIA Display Driver Service (NVSvc) - NVIDIA Corporation - C:\WINDOWS\system32\nvsvc32.exe
O23 - Service: Pml Driver HPZ12 - HP - C:\WINDOWS\system32\HPZipm12.exe
O23 - Service: Acronis Try And Decide Service (TryAndDecideService) - Unknown owner - C:\Programmi\File comuni\Acronis\Fomatik\TrueImageTryStartService.exe
O23 - Service: TrueVector Internet Monitor (vsmon) - Zone Labs, LLC - C:\WINDOWS\system32\ZoneLabs\vsmon.exe

--
End of file - 6216 bytes