NTRootKit-W

This detection covers a device driver that often uses the name m_hook.sys .  The purpose of this trojan is to hide processes and files and terminate various security related programs and services. It is known to be recently distributed with variants of Bagle virus. This trojan gets installed as a service with the name "m_hook". Any attempt to stop the service will create immediate system reboot or BSOD (Blue Screen of Death).

This rootkit hooks into the kernel's System Service Descriptor Table (SSDT) and alters the addresses corresponding to the NTXXX functions implemented in Ntoskrnl.exe.

The following NTXXX functions are replaced with pointers to the rootkit code.

• NTCreateFile
• NTCreateThread
• NTEnumerateKey
• NTEnumerateValueKey
• NTQueryKey
• NTQueryDirectoryFile
• NTQuerySystemInformation

It attempts to terminate following services

• AntiVirScheduler
• AntiVirService
• avgntdd
• avgntmgr
• NISSERV
• filtnt.sys
• guardnt.sys

It attempts to terminate following programs.

_AVPM.EXE
_AVPCC.EXE
_AVP32.EXE
a2guard.exe
aavshield.exe
AckWin32.exe
ADVCHK.EXE
AhnSD.exe
airdefense.exe
ALERTSVC.EXE
ALMon.exe
ALOGSERV.EXE
ALsvc.exe
amon.exe
Anti-Trojan.exe
AntiVirScheduler
AntiVirService
ANTS.EXE
APVXDWIN.EXE
Armor2net.exe
ashAvast.exe
ashDisp.exe
ashEnhcd.exe
ashMaiSv.exe
ashPopWz.exe
ashServ.exe
ashSimpl.exe
ashSkPck.exe
ashWebSv.exe
aswUpdSv.exe
ATCON.EXE
ATUPDATER.EXE
ATWATCH.EXE
AUPDATE.EXE
AUTODOWN.EXE
AUTOTRACE.EXE
AUTOUPDATE.EXE
avciman.exe
Avconsol.exe
AVENGINE.EXE
avgamsvr.exe
avgcc.exe
AVGCC32.EXE
AVGCTRL.EXE
avgemc.exe
avgfwsrv.exe
AVGNT.EXE
AVGSERV.EXE
AVGUARD.EXE
avgupsvc.exe
avinitnt.exe
AvkServ.exe
AVKService.exe
AVKWCtl.exe
AVP.EXE
AVP32.EXE
avpcc.exe
avpm.exe
AVPUPD.EXE
AVSCHED32.EXE
avsynmgr.exe
AVWUPD32.EXE
AVWUPSRV.EXE
AVXMONITOR9X.EXE
AVXMONITORNT.EXE
AVXQUAR.EXE
BackWeb-4476822.exe
bdmcon.exe
bdnews.exe
bdoesrv.exe
bdss.exe
bdsubmit.exe
bdswitch.exe
blackd.exe
blackice.exe
cafix.exe
ccApp.exe
ccEvtMgr.exe
ccProxy.exe
ccSetMgr.exe
CFIAUDIT.EXE
ClamTray.exe
ClamWin.exe
Claw95.exe
Claw95cf.exe
cleaner.exe
cleaner3.exe
CliSvc.exe
CMGrdian.exe
cpd.exe
DefWatch.exe
DOORS.EXE
DrVirus.exe
drwadins.exe
drweb32w.exe
drwebscd.exe
DRWEBUPW.EXE
ESCANH95.EXE
ESCANHNT.EXE
ewidoctrl.exe
EzAntivirusRegistrationCheck.exe
F-AGNT95.EXE
FAMEH32.EXE
FAST.EXE
FCH32.EXE
FireSvc.exe
FireTray.exe
FIREWALL.EXE
fpavupdm.exe
F-PROT95.EXE
freshclam.exe
FRW.EXE
fsav32.exe
fsavgui.exe
fsbwsys.exe
F-Sched.exe
fsdfwd.exe
FSGK32.EXE
fsgk32st.exe
fsguiexe.exe
FSM32.EXE
FSMA32.EXE
FSMB32.EXE
fspex.exe
fssm32.exe
F-StopW.EXE
gcasDtServ.exe
gcasServ.exe
GIANTAntiSpywareMain.exe
GIANTAntiSpywareUpdater.exe
GUARD.EXE
GUARDGUI.EXE
GuardNT.exe
HRegMon.exe
Hrres.exe
HSockPE.exe
HUpdate.EXE
iamapp.exe
iamserv.exe
ICLOAD95.EXE
ICLOADNT.EXE
ICMON.EXE
ICSSUPPNT.EXE
ICSUPP95.EXE
ICSUPPNT.EXE
IFACE.EXE
INETUPD.EXE
InocIT.exe
InoRpc.exe
InoRT.exe
InoTask.exe
InoUpTNG.exe
IOMON98.EXE
isafe.exe
ISATRAY.EXE
ISRV95.EXE
ISSVC.exe
JEDI.EXE
KAV.exe
kavmm.exe
KAVPF.exe
KavPFW.exe
KAVStart.exe
KAVSvc.exe
KAVSvcUI.EXE
KMailMon.EXE
KPfwSvc.EXE
KWatch.EXE
livesrv.exe
LOCKDOWN2000.EXE
LogWatNT.exe
lpfw.exe
LUALL.EXE
LUCOMSERVER.EXE
Luupdate.exe
MCAGENT.EXE
mcmnhdlr.exe
mcregwiz.exe
Mcshield.exe
MCUPDATE.EXE
mcvsshld.exe
MINILOG.EXE
MONITOR.EXE
MonSysNT.exe
MOOLIVE.EXE
MpEng.exe
mpssvc.exe
MSMPSVC.exe
myAgtSvc.exe
myagttry.exe
navapsvc.exe
NAVAPW32.EXE
NavLu32.exe
NAVW32.EXE
NDD32.EXE
NeoWatchLog.exe
NeoWatchTray.exe
NISSERV
NISUM.EXE
NMAIN.EXE
nod32.exe
nod32krn.exe
nod32kui.exe
NORMIST.EXE
notstart.exe
npavtray.exe
NPFMNTOR.EXE
npfmsg.exe
NPROTECT.EXE
NSCHED32.EXE
NSMdtr.exe
NssServ.exe
NssTray.exe
ntrtscan.exe
NTXconfig.exe
NUPGRADE.EXE
NVC95.EXE
Nvcod.exe
Nvcte.exe
Nvcut.exe
NWService.exe
OfcPfwSvc.exe
OUTPOST.EXE
PAV.EXE
PavFires.exe
PavFnSvr.exe
Pavkre.exe
PavProt.exe
pavProxy.exe
pavprsrv.exe
pavsrv51.exe
PAVSS.EXE
pccguide.exe
PCCIOMON.EXE
pccntmon.exe
PCCPFW.exe
PcCtlCom.exe
PCTAV.exe
PERSFW.EXE
pertsk.exe
PERVAC.EXE
PNMSRV.EXE
POP3TRAP.EXE
POPROXY.EXE
prevsrv.exe
PsImSvc.exe
QHM32.EXE
QHONLINE.EXE
QHONSVC.EXE
QHPF.EXE
qhwscsvc.exe
RavMon.exe
RavTimer.exe
Realmon.exe
REALMON95.EXE
Rescue.exe
rfwmain.exe
Rtvscan.exe
RTVSCN95.EXE
RuLaunch.exe
SAVAdminService.exe
SAVMain.exe
savprogress.exe
SAVScan.exe
SCAN32.EXE
ScanningProcess.exe
sched.exe
sdhelp.exe
SERVIC~1.EXE
SHSTAT.EXE
SiteCli.exe
smc.exe
SNDSrvc.exe
SPBBCSvc.exe
SPHINX.EXE
spiderml.exe
spidernt.exe
Spiderui.exe
SpybotSD.exe
SPYXX.EXE
SS3EDIT.EXE
stopsignav.exe
swAgent.exe
swdoctor.exe
SWNETSUP.EXE
symlcsvc.exe
SymProxySvc.exe
SymSPort.exe
SymWSC.exe
SYNMGR.EXE
TAUMON.EXE
TBMon.exe
TC.EXE
tca.exe
TCM.EXE
TDS-3.EXE
TeaTimer.exe
TFAK.EXE
THAV.EXE
THSM.EXE
Tmas.exe
tmlisten.exe
Tmntsrv.exe
TmPfw.exe
tmproxy.exe
TNBUtil.exe
TRJSCAN.EXE
Up2Date.exe
UPDATE.EXE
UpdaterUI.exe
upgrepl.exe
Vba32ECM.exe
Vba32ifs.exe
vba32ldr.exe
Vba32PP3.exe
VBSNTW.exe
vchk.exe
vcrmon.exe
VetTray.exe
VirusKeeper.exe
VPTRAY.EXE
vrfwsvc.exe
VRMONNT.EXE
vrmonsvc.exe
vrrw32.exe
VSECOMR.EXE
Vshwin32.exe
vsmon.exe
vsserv.exe
VsStat.exe
WATCHDOG.EXE
WebProxy.exe
Webscanx.exe
WEBTRAP.EXE
WGFE95.EXE
Winaw32.exe
winroute.exe
winss.exe
winssnotify.exe
WRADMIN.EXE
WRCTRL.EXE
xcommsvr.exe
zatutor.exe
ZAUINST.EXE
zlclient.exe
zonealarm.exe

• Unexpected termination of antivirus and security products.

Registry Changes - most relevant

• HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Enum\Root\LEGACY_M_HOOK\0000\ClassGUID: "{8ECC055D-047F-11D1-A537-0000F8753ED1}"
• HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Enum\Root\LEGACY_M_HOOK\0000\DeviceDesc: "M_HOOK"
• HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\M_HOOK\ImagePath: "\??\C:\Documents and Settings\Administrator\Desktop\M_HOOK.SYS"
• HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\M_HOOK\DisplayName: "M_HOOK"
• HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
  Enum\Root\LEGACY_M_HOOK\0000\ClassGUID: "{8ECC055D-047F-11D1-A537-0000F8753ED1}"
• HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
  Enum\Root\LEGACY_M_HOOK\0000\DeviceDesc: "M_HOOK"
• HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
  Services\M_HOOK\ImagePath: "\??\C:\Documents and Settings\Administrator\Desktop\M_HOOK.SYS"
• HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
  Services\M_HOOK\DisplayName: "M_HOOK"
  

This trojan may be distributed with W32/Bagle variants and other malware.

All Users:

Please use the following instructions for all supported versions of Windows to remove threats and other potential risks:

1.Disable System Restore .

2.Update to current engine and DAT files for detection and removal.

3.Run a complete system scan.

Modifications made to the system Registry and/or INI files for the purposes of hooking system startup, will be successfully removed if cleaning with the recommended engine and DAT combination (or higher).

1. Please go to the Microsoft Recovery Console and restore a clean MBR.

On windows XP:

Insert the Windows XP CD into the CD-ROM drive and restart the computer.
When the "Welcome to Setup" screen appears, press R to start the Recovery Console.
Select the Windows installation that is compromised and provide the administrator password
Issue 'fixmbr' command to restore the Master Boot Record
Follow onscreen instructions
Reset and remove the CD from CD-ROM drive.