Topic: strani file in c:windows

aprendo la cartella citata in oggetto mi sono accorto dell'esistenza di svariati file che pur non essendo un fenomeno mi sembrano strani eccoli: grep.exe - mbr.exe - nircmd.exe - pev.exe - sed.exe - slrundll.exe - swreg.exe - swsc.exe - swxcalcs.exe - taskman.exe - zip.exe, sono pericolosi? come posso farli sparire? vi allego anche un Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 11.00.51, on 03/02/2010
Platform: Windows XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v8.00 (8.00.6001.18702)
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:\Programmi\COMODO\COMODO Internet Security\cmdagent.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\spoolsv.exe
C:\Programmi\Avira\AntiVir Desktop\sched.exe
C:\WINDOWS\Explorer.EXE
C:\Programmi\Avira\AntiVir Desktop\avguard.exe
C:\WINDOWS\system32\oodag.exe
C:\WINDOWS\system32\svchost.exe
C:\Programmi\Avira\AntiVir Desktop\avgnt.exe
C:\WINDOWS\system32\rundll32.exe
C:\Programmi\COMODO\COMODO Internet Security\cfp.exe
C:\Programmi\hijackthis\HijackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.libero.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,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 - HKCU\Software\Microsoft\Internet Explorer\Main,Local Page =
R0 - HKLM\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: HelperObject Class - {00C6482D-C502-44C8-8409-FCE54AD9C208} - C:\Programmi\TechSmith\SnagIt 7\SnagItBHO.dll
O2 - BHO: Search Helper - {6EBF7485-159F-4bff-A14F-B9E3AAC4465B} - C:\Programmi\Microsoft\Search Enhancement Pack\Search Helper\SEPsearchhelperie.dll
O2 - BHO: Guida per l'accesso a Windows Live - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Programmi\File comuni\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: Java(tm) Plug-In 2 SSV Helper - {DBC80044-A445-435b-BC74-9C25C1C588A9} - C:\Programmi\Java\jre6\bin\jp2ssv.dll
O4 - HKLM\..\Run: [OODefragTray] C:\WINDOWS\system32\oodtray.exe
O4 - HKLM\..\Run: [avgnt] "C:\Programmi\Avira\AntiVir Desktop\avgnt.exe" /min /nosplash
O4 - HKLM\..\Run: [CnxTrApp] rundll32.exe "C:\Programmi\StarModem\StarModem USB Network\CnxTrApp.dll",AppEntry -REG "Conexant\Conexant USB Network"
O4 - HKLM\..\Run: [COMODO Internet Security] "C:\Programmi\COMODO\COMODO Internet Security\cfp.exe" -h
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')
O4 - Startup: ERUNT AutoBackup.lnk = C:\Programmi\ERUNT\AUTOBACK.EXE
O9 - Extra button: Ricerche - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MI1933~1\OFFICE11\REFIEBAR.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
O20 - AppInit_DLLs:       C:\WINDOWS\system32\guard32.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: COMODO Internet Security Helper Service (cmdAgent) - COMODO - C:\Programmi\COMODO\COMODO Internet Security\cmdagent.exe
O23 - Service: O&O Defrag - O&O Software GmbH - C:\WINDOWS\system32\oodag.exe

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