Change log for definition version 1.251.911.0 RSS feed icon

This page lists what has changed in the most recent definitions update for Windows Defender Antivirus and Microsoft Security Essentials.

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The following tables list the new and updated definitions for the version you select here. You can choose from the 20 latest updates, and the most recent update is shown by default:

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Definition available date: Sep 13,2017 11:44 PM UTC

New definitions

Updated definitions

HackTool:MSIL/Boilod.Ahigh
SoftwareBundler:MSIL/Wizremhigh
SoftwareBundler:Win32/ICLoaderhigh
SoftwareBundler:Win32/Mizenotahigh
TrojanDownloader:Win32/Delfhigh
TrojanDownloader:Win32/QQHelper.KAhigh
Backdoor:MSIL/Bladabindi!rfnsevere
Backdoor:MSIL/Noancooe.Csevere
Backdoor:Win32/Bergat.Asevere
Backdoor:Win32/Bifrosesevere
Backdoor:Win32/Ciadoorsevere
Backdoor:Win32/Crugup.Bsevere
Backdoor:Win32/Cycbot.Bsevere
Backdoor:Win32/Darkmoon.AEsevere
Backdoor:Win32/Delfsnifsevere
Backdoor:Win32/Kirts.Asevere
Backdoor:Win32/Mangwam.Asevere
Backdoor:Win32/Mosucker.AAsevere
Backdoor:Win32/Nosrawec.Asevere
Backdoor:Win32/PcClientsevere
Backdoor:Win32/Qakbot!rfnsevere
Backdoor:Win32/Qakbot.Tsevere
Backdoor:Win32/Simbotsevere
Backdoor:Win32/Turkojansevere
Backdoor:Win32/VBsevere
Backdoor:Win32/Xtrat.ACsevere
Backdoor:Win32/Zegostsevere
DDoS:Win32/Nitol.Asevere
DDoS:Win32/Nitol.Bsevere
Exploit:JS/Axpergle!rfnsevere
Exploit:Win32/Shellcodesevere
PWS:HTML/Phishsevere
PWS:Win32/Beomok.Asevere
PWS:Win32/Dyzap.Xsevere
PWS:Win32/Fareitsevere
PWS:Win32/Fignotok.Asevere
PWS:Win32/Lmirsevere
PWS:Win32/OnLineGamessevere
PWS:Win32/Perfwo.B.dllsevere
PWS:Win32/Sapbexts.Bsevere
PWS:Win32/Sekur.Asevere
PWS:Win32/Stealer.Msevere
Ransom:Win32/Ergop.Asevere
Ransom:Win32/LockScreensevere
Ransom:Win32/Wadhramasevere
Rogue:Win32/Winwebsecsevere
Trojan:BAT/Startpage.Gsevere
Trojan:Java/Adwindsevere
Trojan:JS/Redirector!rfnsevere
Trojan:MSIL/Blinerarch.AYsevere
Trojan:MSIL/Eskimo.Asevere
Trojan:MSIL/Injector.SO!bitsevere
Trojan:O97M/Madeba!rfnsevere
Trojan:Win32/Alureonsevere
Trojan:Win32/Alureon!infsevere
Trojan:Win32/Carberp.Ksevere
Trojan:Win32/Dogrobotsevere
Trojan:Win32/Dorv.Asevere
Trojan:Win32/Ertfor.Asevere
Trojan:Win32/Gataka.Dsevere
Trojan:Win32/Gemalind.A!bitsevere
Trojan:Win32/Killfilessevere
Trojan:Win32/Lethic.Gsevere
Trojan:Win32/Multsarch.Vsevere
Trojan:Win32/Nedsym!hostsevere
Trojan:Win32/Rebhip.AA!bitsevere
Trojan:Win32/Riern.Lsevere
Trojan:Win32/Vicenorsevere
Trojan:Win32/Zonsterarch!rfnsevere
Trojan:Win32/Zonsterarch.ACsevere
Trojan:Win32/Zonsterarch.BWsevere
Trojan:Win64/SvcMiner.Asevere
Trojan:WinNT/Alureon.Hsevere
TrojanClicker:Win32/Frosparf.Fsevere
TrojanDownloader:MSIL/Gendwnurl!rfnsevere
TrojanDownloader:O97M/Donoffsevere
TrojanDownloader:Win32/Agentsevere
TrojanDownloader:Win32/Brantall!rfnsevere
TrojanDownloader:Win32/Dofoil!rfnsevere
TrojanDownloader:Win32/Dofoil.ACsevere
TrojanDownloader:Win32/FakeIE.Bsevere
TrojanDownloader:Win32/Tugspay.Asevere
TrojanDownloader:Win32/Vitero.Asevere
TrojanDownloader:Win32/Waledac.ALsevere
TrojanDropper:BAT/Startpage.Asevere
TrojanDropper:Win32/Dowque.Asevere
TrojanDropper:Win32/Randrew.A!bitsevere
TrojanDropper:Win32/Woozlist.Bsevere
TrojanProxy:Win32/Rasersevere
TrojanSpy:MSIL/Golroted.Asevere
TrojanSpy:MSIL/Golroted.Bsevere
TrojanSpy:MSIL/Golroted.Esevere
TrojanSpy:MSIL/Golroted.Fsevere
TrojanSpy:MSIL/Lesat.Asevere
TrojanSpy:MSIL/Omaneat.Bsevere
TrojanSpy:MSIL/Plimrost.Bsevere
TrojanSpy:MSIL/VB.Fsevere
TrojanSpy:Win32/Lydrasevere
TrojanSpy:Win32/Nivdort!rfnsevere
TrojanSpy:Win32/Rebhip.Csevere
TrojanSpy:Win32/Usteal.Dsevere
TrojanSpy:Win32/Vwealersevere
TrojanSpy:WinNT/Ardamax.A!syssevere
VirTool:MSIL/Subti.Nsevere
VirTool:Win32/CeeInjectsevere
VirTool:Win32/DelfInjectsevere
VirTool:Win32/Injectorsevere
VirTool:Win32/Vbcryptsevere
VirTool:Win32/VBInjectsevere
Worm:AutoIt/Nuqelsevere
Worm:MSIL/Ainslot.Asevere
Worm:Win32/Ainslot.Asevere
Worm:Win32/Autorunsevere
Worm:Win32/Gamarue!rfnsevere
Worm:Win32/Mocmexsevere
Worm:Win32/Mofksys.Asevere
Worm:Win32/NewWormsevere
Worm:Win32/Nuj.Asevere
Worm:Win32/Prolacosevere
Worm:Win32/Rebhipsevere
Worm:Win32/Slenpingsevere
Worm:Win32/Soltern.ACsevere
Worm:Win32/VBsevere
Worm:Win32/Wahrecks.Asevere
Worm:Win32/Yoybotsevere