Puoi anche postare (ti verrà risposto, stai tranquillo) senza problemi nella specifica Sezione "Virus, sicurezza e privacy", questo tuo problema.
Ma aggiungi alcune cose che sono davvero fondamentali:
1) che Sistema Operativo usi? (e quale Service Pack hai installato?)
2) che firewall usi?
3) che antivirus usi?
4) quali sintomi ESATTAMENTE (non descriverli "troppo genericamente", cerca d'essere un pochino più preciso e dettagliato, se possibile: e spiega anche a partire da quando han cominciato a manifestarsi) rilevi sul tuo PC?
Fai queste cose (il LOG di HijackThis [così come altrii LOGs] probabilmente servirà anche lui, ma non è sempre vero che sia una sorta di "panacea universale"... e men che meno una "dieta fissa" da dover seguire "a priori" sempre e comunque) potremo cominciare a ragionare sul problema.

Logfile of Trend Micro HijackThis v2.0.4
Scan saved at 7.03.27, on 24/07/2010
Platform: Windows XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.17055)
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\svchost.exe
C:\Programmi\Avira\AntiVir Desktop\sched.exe
C:\WINDOWS\Explorer.EXE
C:\Programmi\Avira\AntiVir Desktop\avgnt.exe
C:\Programmi\Avira\AntiVir Desktop\avguard.exe
C:\WINDOWS\system32\svchost.exe
C:\Programmi\Avira\AntiVir Desktop\avscan.exe
C:\abc\CF27566.cfxxe
C:\Programmi\File comuni\Microsoft Shared\Windows Live\WLIDSVC.EXE
C:\Programmi\Microsoft Office\OFFICE11\WINWORD.EXE
C:\Programmi\File comuni\Microsoft Shared\Windows Live\WLIDSvcM.exe
C:\WINDOWS\system32\spoolsv.exe
C:\Programmi\Outlook Express\msimn.exe
C:\WINDOWS\system32\CNAB4RPK.EXE
C:\Programmi\freeTVRadio\spointer\freetvradio_air.exe
C:\Programmi\Mozilla Firefox\firefox.exe
C:\abc\ATTRIB.cfxxe
C:\WINDOWS\system32\msiexec.exe
C:\Programmi\Trend Micro\HijackThis\HiJackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = http://www.crawler.com/search/dispatcher.aspx?tp=aus&qkw=%s&tbid=60341
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.google.it/
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,SearchAssistant = http://www.crawler.com/search/ie.aspx?tb_id=60341
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,CustomizeSearch = http://dnl.crawler.com/support/sa_customize.aspx?TbId=60341
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 = http://www.crawler.com/search/ie.aspx?tb_id=60341
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,CustomizeSearch = http://dnl.crawler.com/support/sa_customize.aspx?TbId=60341
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings,ProxyOverride = *.local
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Collegamenti
R3 - URLSearchHook: Yahoo! Toolbar con blocco Pop-Up - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - (no file)
R3 - URLSearchHook: Softonic-IT Toolbar - {e3393495-8103-46a0-8181-270273eddd60} - C:\Programmi\Softonic-IT\tbSof1.dll
O2 - BHO: AcroIEHelperStub - {18DF081C-E8AD-4283-A596-FA578C2EBDC3} - C:\Programmi\File comuni\Adobe\Acrobat\ActiveX\AcroIEHelperShim.dll
O2 - BHO: (no name) - {3049C3E9-B461-4BC5-8870-4C09146192CA} - (no file)
O2 - BHO: Interest recogniser for Freetvradio (powered by Spointer) - {4C4AD71D-52E1-4402-9E5B-CBFC295EC9BA} - C:\Programmi\freeTVRadio\spointer\extensions\freetvradio_air_ie.dll
O2 - BHO: Spybot-S&D IE Protection - {53707962-6F74-2D53-2644-206D7942484F} - C:\Programmi\Spybot - Search & Destroy\SDHelper.dll
O2 - BHO: (no name) - {5C255C8A-E604-49b4-9D64-90988571CECB} - (no file)
O2 - BHO: Windows Live ID Sign-in Helper - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Programmi\File comuni\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: AcroIEToolbarHelper Class - {AE7CD045-E861-484f-8273-0445EE161910} - C:\Programmi\Adobe\Acrobat 6.0\Acrobat\AcroIEFavClient.dll
O2 - BHO: Java(tm) Plug-In 2 SSV Helper - {DBC80044-A445-435b-BC74-9C25C1C588A9} - C:\Programmi\Java\jre6\bin\jp2ssv.dll
O2 - BHO: Softonic-IT Toolbar - {e3393495-8103-46a0-8181-270273eddd60} - C:\Programmi\Softonic-IT\tbSof1.dll
O2 - BHO: JQSIEStartDetectorImpl - {E7E6F031-17CE-4C07-BC86-EABFE594F69C} - C:\Programmi\Java\jre6\lib\deploy\jqs\ie\jqs_plugin.dll
O3 - Toolbar: Adobe PDF - {47833539-D0C5-4125-9FA8-0819E2EAAC93} - C:\Programmi\Adobe\Acrobat 6.0\Acrobat\AcroIEFavClient.dll
O3 - Toolbar: (no name) - {CCC7A320-B3CA-4199-B1A6-9F516DD69829} - (no file)
O3 - Toolbar: Softonic-IT Toolbar - {e3393495-8103-46a0-8181-270273eddd60} - C:\Programmi\Softonic-IT\tbSof1.dll
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\system32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [NvMediaCenter] RUNDLL32.EXE C:\WINDOWS\system32\NvMcTray.dll,NvTaskbarInit
O4 - HKLM\..\Run: [BluetoothAuthenticationAgent] rundll32.exe bthprops.cpl,,BluetoothAuthenticationAgent
O4 - HKLM\..\Run: [RTHDCPL] RTHDCPL.EXE
O4 - HKLM\..\Run: [Alcmtr] ALCMTR.EXE
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Programmi\Java\jre6\bin\jusched.exe"
O4 - HKLM\..\Run: [QuickTime Task] "C:\Programmi\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [KernelFaultCheck] %systemroot%\system32\dumprep 0 -k
O4 - HKLM\..\Run: [avgnt] "C:\Programmi\Avira\AntiVir Desktop\avgnt.exe" /min
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [PC Suite Tray] "C:\Programmi\Nokia\Nokia PC Suite 7\PCSuite.exe" -onlytray
O4 - HKCU\..\Run: [{4CC1E084-9A6D-4EA8-DF5D-84E6FA62F176}] "C:\Documents and Settings\utente\Dati applicazioni\Eqhu\wufi.exe"
O4 - HKUS\S-1-5-18\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'Default user')
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: Invia a &Bluetooth - C:\Programmi\WIDCOMM\Software Bluetooth\btsendto_ie_ctx.htm
O8 - Extra context menu item: Scarica link utilizzando Mega Manager... - C:\Programmi\Megaupload\Mega Manager\mm_file.htm
O9 - Extra button: Ricerche - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\OFFICE11\REFIEBAR.DLL
O9 - Extra button: @btrez.dll,-4015 - {CCA281CA-C863-46ef-9331-5C8D4460577F} - C:\Programmi\WIDCOMM\Software Bluetooth\btsendto_ie.htm
O9 - Extra 'Tools' menuitem: @btrez.dll,-4017 - {CCA281CA-C863-46ef-9331-5C8D4460577F} - C:\Programmi\WIDCOMM\Software Bluetooth\btsendto_ie.htm
O9 - Extra button: (no name) - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\Programmi\Spybot - Search & Destroy\SDHelper.dll
O9 - Extra 'Tools' menuitem: Spybot - Search && Destroy Configuration - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\Programmi\Spybot - Search & Destroy\SDHelper.dll
O9 - Extra button: (no name) - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe (file missing)
O9 - Extra 'Tools' menuitem: @xpsp3res.dll,-20001 - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe (file missing)
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Programmi\Messenger\msmsgs.exe (file missing)
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Programmi\Messenger\msmsgs.exe (file missing)
O16 - DPF: {5ED80217-570B-4DA9-BF44-BE107C0EC166} (Windows Live Safety Center Base Module) - http://cdn.scan.onecare.live.com/resource/download/scanner/wlscbase8942.cab
O22 - SharedTaskScheduler: Precaricatore Browseui - {438755C2-A8BA-11D1-B96B-00A0C90312E1} - C:\WINDOWS\system32\browseui.dll
O22 - SharedTaskScheduler: Daemon di cache delle categorie di componenti - {8C7461EF-2B13-11d2-BE35-3078302C2030} - C:\WINDOWS\system32\browseui.dll
O23 - Service: Avira AntiVir Scheduler (AntiVirScheduler) - Avira GmbH - C:\Programmi\Avira\AntiVir Desktop\sched.exe
O23 - Service: Avira AntiVir Guard (AntiVirService) - Avira GmbH - C:\Programmi\Avira\AntiVir Desktop\avguard.exe
O23 - Service: Ati HotKey Poller - Unknown owner - C:\WINDOWS\system32\Ati2evxx.exe (file missing)
O23 - Service: ATI Smart - Unknown owner - C:\WINDOWS\system32\ati2sgag.exe (file missing)
O23 - Service: iPod Service - Apple Inc. - C:\Programmi\iPod\bin\iPodService.exe
O23 - Service: LEC TranslateDotNet Server - Language Engineering Corporation, LLC - C:\Programmi\Power Translator\LogoMedia TranslateDotNet Server.exe
O23 - Service: LightScribeService Direct Disc Labeling Service (LightScribeService) - Unknown owner - C:\Programmi\File comuni\LightScribe\LSSrvc.exe (file missing)
O23 - Service: MBAMService - Malwarebytes Corporation - C:\Programmi\Malwarebytes' Anti-Malware\mbamservice.exe
O23 - Service: McAfee Security Scan Component Host Service (McComponentHostService) - McAfee, Inc. - C:\Programmi\McAfee Security Scan\2.0.181\McCHSvc.exe
O23 - Service: NVIDIA Display Driver Service (NVSvc) - Unknown owner - C:\WINDOWS\system32\nvsvc32.exe (file missing)
O23 - Service: PDAgent - Raxco Software, Inc. - C:\Programmi\Raxco\PerfectDisk10\PDAgent.exe
O23 - Service: PDEngine - Raxco Software, Inc. - C:\Programmi\Raxco\PerfectDisk10\PDEngine.exe
O23 - Service: Cyberlink RichVideo Service(CRVS) (RichVideo) - Unknown owner - C:\Programmi\CyberLink\Shared Files\RichVideo.exe (file missing)
O23 - Service: ServiceLayer - Nokia - C:\Programmi\PC Connectivity Solution\ServiceLayer.exe

--
End of file - 9247 bytes

C:\abc\CF27566.cfxxe

estremamente sospetto... non so aiutarti perchè non uso winzozz, ma qualche winzozziano esperto potrtà darti qualche dritta...

---

Sono cosi avanti che quando guardo indietro vedo il futuro.

Ecco (in inglese) un'analisi concernente una tipo di situazione probabilmente affine: Threat Expert Report.

Questo chiarisce molto in proposito.

http://www.ismprofessional.net/pascucci/documenti/linux-virus/
Bilodiego

È lunghisssimol'articolo,quindi è normale che tu non l'abbia letto ,infatti prospetta quello che potrebbe accadere presto o tardi.
Bilodiego

@
molte persone contribuiscono, perchè in questo caso "ubuntu" a un codice aperto ovvero molti altri possono controllare e si rischia di rimetterci la faccia, quindi in nesuna riga può celarsi un virus il luogo della discussione è LINUX - Ubuntu e derivati oppure Amici di IstitutoMajorana perchè no . chissà forse ne esce un bellisimo topik