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  3. W32.Mytob.EH@mm

W32.Mytob.EH@mm

Risk Level 2: Low

Discovered:
June 13, 2005
Updated:
June 13, 2005 1:00:11 PM
Systems Affected:
Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows XP
W32.Mytob.EH@mm is a mass-mailing worm that opens an IRC back door and lowers security settings on the compromised computer.

Once executed, the worm copies itself as the following:
%System%\msdev32.exe

The worm creates the following registry entries so that it runs every time Windows starts:
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run\"WINDOWS SYSTEM" = "msdev32.exe"
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunServices\"WINDOWS SYSTEM" = "msdev32.exe"

The worm adds the following registry entry to disable the Shared Access service in Windows 2000/XP:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\SharedAccess\"Start" = "4"

The worm continually recreates these registry keys if they are deleted.

The worm creates the following mutex so that only one instance of the worm is run on the compromised computer:
H-E-L-L-B-O-T-P-O-L-Y-M-O-R-P-H

The worm gathers email addresses from the Windows Address Book and from the following locations:
%Windir%\Temporary Internet Files
%Userprofile%\Local Settings\Temporary Internet Files
%System%

The worm also gathers email addresses from files with the following extensions on all local drives from C to Y:
.adb
.asp
.cgi
.dbx
.htm
.jsp
.php
.sht
.tbb
.txt
.wab
.xml

The worm will not send itself to email addresses that contain any of the following strings:
abuse
accoun
admin
anyone
bsd
bugs
certific
contact
spam
feste
gold-certs
google
help
icrosoft
info
linux
listserv
nobody
noone
not
nothing
ntivi
page
postmaster
privacy
rating
root
samples
secur
service
site
soft
somebody
someone
spm
submit
support
the.bat
unix
webmaster
www
you
your

The worm will not send itself to email addresses that contain any of the following domain names:
.edu
.gov
.mil
acketst
arin.
avp
be_loyal:
berkeley
borlan
bsd
example
fido
foo.
fsf.
gnu
google
gov.
hotmail
iana
ibm.com
icrosof
ietf
inpris
isc.o
isi.e
kernel
linux
math
mit.e
mozilla
msn.
mydomai
nodomai
panda
pgp
rfc-ed
ripe.
ruslis
secur
sendmail
sopho
syma
tanford.e
unix
usenet
utgers.ed

The worm may append the following prefixes to domain names in an attempt to find Simple Mail Transfer Protocol (SMTP) servers:
gate.
mail.
mail1.
mx.
mx1.
mxs.
ns.
relay.
smtp.

The worm then uses its own SMTP engine to send itself to the email addresses that it finds. The email has the following characteristics:

From:
One of the following:
adam
alex
andrew
anna
bill
bob
bob
brenda
brent
brian
claudia
dan
dave
david
debby
frank
fred
george
helen
jack
james
jane
jerry
jim
jimmy
joe
john
jose
josh
julie
kevin
leo
linda
maria
mary
matt
michael
michael
mike
paul
peter
ray
robert
sales
sam
sandra
serg
smith
stan
steve
ted
tom

The worm may also spoof an address by appending one of the following stings to the domain of the target email address:
admin
administrator
info
mail
register
service
support
webmaster

Subject:
One of the following:
Your Account is Suspended
*DETECTED* Online User Violation
Your Account is Suspended For Security Reasons
Warning Message: Your services near to be closed.
Important Notification
Members Support
Security measures
Email Account Suspension
Notice of account limitation
[random characters]

Message:
One of the following:
Dear user [username],
You have successfully updated the password of your [domain] account.
If you did not authorize this change or if you need assistance with your account, please contact [domain] customer service at: [full domain]
Thank you for using [domain]!
The [domain] Support Team

Dear user [username],
It has come to our attention that your [domain] User Profile ( x ) records are out of date. For further details see the attached document.
Thank you for using [domain]!
The [domain] Support Team
+++ Attachment: No Virus (Clean)
+++ [domain] Antivirus - www.[full domain]

Dear [domain] Member,
We have temporarily suspended your email account [username].
This might be due to either of the following reasons:
1. A recent change in your personal information (i.e. change of address).
2. Submiting invalid information during the initial sign up process.
3. An innability to accurately verify your selected option of subscription due to an internal error within our processors.
See the details to reactivate your [domain] account.
Sincerely,The [domain] Support Team
+++ Attachment: No Virus (Clean)
+++ [domain] Antivirus - www.[full domain]

Dear [domain] Member,
Your e-mail account was used to send a huge amount of unsolicited spam messages during the recent week. If you could please take 5-10 minutes out of your online experience and confirm the attached document so you will not run into any future problems with the online service.
If you choose to ignore our request, you leave us no choice but to cancel your membership.
Virtually yours,
The [domain] Support Team
+++ Attachment: No Virus found
+++ [domain] Antivirus - www.[full domain]

Where [username] is the user part of the target e-mail address and [domain] is the domain part of the target email address.

Attachment:
One of the following:
accepted-password
account-details
account-info
account-password
account-repotr
approved-password
document
email-details
email-password
important-details
new-password
password
readme
updated-password
[random name]

with one of the following as an extension:
.pif
.scr
.exe
.bat
.cmd

The worm may also send a zip copy of itself. The zipped file will have .doc, .htm, or .txt as the first extension name and .exe, .pif, or .scr as the second extension name.

Next, the worm connects to an IRC channel on TCP port 5232 on the host l33t.freeshellz.org and listen for commands that allow the remote attacker to perform the following actions:
Execute files
Download files
Perform other IRC commands determined by the attacker
Reboot the compromised computer

The worm blocks access to several security-related Web sites by appending the following text to the hosts file:
127.0.0.1 www.symantec.com
127.0.0.1 securityresponse.symantec.com
127.0.0.1 symantec.com
127.0.0.1 www.sophos.com
127.0.0.1 sophos.com
127.0.0.1 www.mcafee.com
127.0.0.1 mcafee.com
127.0.0.1 liveupdate.symantecliveupdate.com
127.0.0.1 www.viruslist.com
127.0.0.1 viruslist.com
127.0.0.1 viruslist.com
127.0.0.1 f-secure.com
127.0.0.1 www.f-secure.com
127.0.0.1 kaspersky.com
127.0.0.1 kaspersky-labs.com
127.0.0.1 www.avp.com
127.0.0.1 www.kaspersky.com
127.0.0.1 avp.com
127.0.0.1 www.networkassociates.com
127.0.0.1 networkassociates.com
127.0.0.1 www.ca.com
127.0.0.1 ca.com
127.0.0.1 mast.mcafee.com
127.0.0.1 my-etrust.com
127.0.0.1 www.my-etrust.com
127.0.0.1 download.mcafee.com
127.0.0.1 dispatch.mcafee.com
127.0.0.1 secure.nai.com
127.0.0.1 nai.com
127.0.0.1 www.nai.com
127.0.0.1 update.symantec.com
127.0.0.1 updates.symantec.com
127.0.0.1 us.mcafee.com
127.0.0.1 liveupdate.symantec.com
127.0.0.1 customer.symantec.com
127.0.0.1 rads.mcafee.com
127.0.0.1 trendmicro.com
127.0.0.1 pandasoftware.com
127.0.0.1 www.pandasoftware.com
127.0.0.1 www.trendmicro.com
127.0.0.1 www.grisoft.com
127.0.0.1 www.microsoft.com
127.0.0.1 microsoft.com
127.0.0.1 www.virustotal.com
127.0.0.1 virustotal.com
127.0.0.1 www.amazon.com
127.0.0.1 www.amazon.co.uk
127.0.0.1 www.amazon.ca
127.0.0.1 www.amazon.fr
127.0.0.1 www.paypal.com
127.0.0.1 paypal.com
127.0.0.1 moneybookers.com
127.0.0.1 www.moneybookers.com
127.0.0.1 www.ebay.com
127.0.0.1 ebay.com

The worm also attempts to end the following processes, some of which may be security-related:
ACKWIN32.EXE
ADAWARE.EXE
ADVXDWIN.EXE
AGENTSVR.EXE
AGENTW.EXE
ALERTSVC.EXE
ALEVIR.EXE
ALOGSERV.EXE
AMON9X.EXE
ANTI-TROJAN.EXE
ANTIVIRUS.EXE
ANTS.EXE
APIMONITOR.EXE
APLICA32.EXE
APVXDWIN.EXE
ARR.EXE
ATCON.EXE
ATGUARD.EXE
ATRO55EN.EXE
ATUPDATER.EXE
ATUPDATER.EXE
ATWATCH.EXE
AU.EXE
AUPDATE.EXE
AUPDATE.EXE
AUTODOWN.EXE
AUTODOWN.EXE
AUTOTRACE.EXE
AUTOTRACE.EXE
AUTOUPDATE.EXE
AUTOUPDATE.EXE
AVCONSOL.EXE
AVE32.EXE
AVGCC32.EXE
AVGCTRL.EXE
AVGNT.EXE
AVGSERV.EXE
AVGSERV9.EXE
AVGUARD.EXE
AVGW.EXE
AVKPOP.EXE
AVKSERV.EXE
AVKSERVICE.EXE
AVKWCTl9.EXE
AVLTMAIN.EXE
AVNT.EXE
AVP.EXE
AVP32.EXE
AVPCC.EXE
AVPDOS32.EXE
AVPM.EXE
AVPTC32.EXE
AVPUPD.EXE
AVPUPD.EXE
AVSCHED32.EXE
AVSYNMGR.EXE
AVWINNT.EXE
AVWUPD.EXE
AVWUPD32.EXE
AVWUPD32.EXE
AVWUPSRV.EXE
AVXMONITOR9X.EXE
AVXMONITORNT.EXE
AVXQUAR.EXE
AVXQUAR.EXE
BACKWEB.EXE
BARGAINS.EXE
BD_PROFESSIONAL.EXE
BEAGLE.EXE
BELT.EXE
BIDEF.EXE
BIDSERVER.EXE
BIPCP.EXE
BIPCPEVALSETUP.EXE
BISP.EXE
BLACKD.EXE
BLACKICE.EXE
BLSS.EXE
BOOTCONF.EXE
BOOTWARN.EXE
BORG2.EXE
BPC.EXE
BRASIL.EXE
BS120.EXE
BUNDLE.EXE
BVT.EXE
CCAPP.EXE
CCEVTMGR.EXE
CCPXYSVC.EXE
CDP.EXE
CFD.EXE
CFGWIZ.EXE
CFIADMIN.EXE
CFIAUDIT.EXE
CFIAUDIT.EXE
CFINET.EXE
CFINET32.EXE
CLEAN.EXE
CLEANER.EXE
CLEANER3.EXE
CLEANPC.EXE
CLICK.EXE
CMD32.EXE
CMESYS.EXE
CMGRDIAN.EXE
CMON016.EXE
CONNECTIONMONITOR.EXE
CPD.EXE
CPF9X206.EXE
CPFNT206.EXE
CTRL.EXE
CV.EXE
CWNB181.EXE
CWNTDWMO.EXE
CLAW95CF.EXE
DATEMANAGER.EXE
DCOMX.EXE
DEFALERT.EXE
DEFSCANGUI.EXE
DEFWATCH.EXE
DEPUTY.EXE
DIVX.EXE
DLLCACHE.EXE
DLLREG.EXE
DOORS.EXE
DPF.EXE
DPFSETUP.EXE
DPPS2.EXE
DRWATSON.EXE
DRWEB32.EXE
DRWEBUPW.EXE
DSSAGENT.EXE
DVP95.EXE
DVP95_0.EXE
ECENGINE.EXE
EFPEADM.EXE
EMSW.EXE
ENT.EXE
ESAFE.EXE
ESCANHNT.EXE
ESCANV95.EXE
ESPWATCH.EXE
ETHEREAL.EXE
ETRUSTCIPE.EXE
EVPN.EXE
EXANTIVIRUS-CNET.EXE
EXE.AVXW.EXE
EXPERT.EXE
EXPLORE.EXE
F-PROT.EXE
F-PROT95.EXE
F-STOPW.EXE
FAMEH32.EXE
FAST.EXE
FCH32.EXE
FIH32.EXE
FINDVIRU.EXE
FIREWALL.EXE
FNRB32.EXE
FP-WIN.EXE
FP-WIN_TRIAL.EXE
FPROT.EXE
FRW.EXE
FSAA.EXE
FSAV.EXE
FSAV32.EXE
FSAV530STBYB.EXE
FSAV530WTBYB.EXE
FSAV95.EXE
FSGK32.EXE
FSM32.EXE
FSMA32.EXE
FSMB32.EXE
GATOR.EXE
GBMENU.EXE
GBPOLL.EXE
GENERICS.EXE
GMT.EXE
GUARD.EXE
GUARDDOG.EXE
HACKTRACERSETUP.EXE
HBINST.EXE
HBSRV.EXE
HOTACTIO.EXE
HOTPATCH.EXE
HTLOG.EXE
HTPATCH.EXE
HWPE.EXE
HXDL.EXE
HXIUL.EXE
IAMAPP.EXE
IAMSERV.EXE
IAMSTATS.EXE
IBMASN.EXE
IBMAVSP.EXE
ICLOADNT.EXE
ICMON.EXE
ICSUPP95.EXE
ICSUPPNT.EXE
IDLE.EXE
IEDLL.EXE
IEDRIVER.EXE
IEXPLORER.EXE
IFACE.EXE
IFW2000.EXE
INETLNFO.EXE
INFUS.EXE
INFWIN.EXE
INIT.EXE
INTDEL.EXE
INTREN.EXE
IOMON98.EXE
ISTSVC.EXE
JAMMER.EXE
JDBGMRG.EXE
JEDI.EXE
KAVLITE40ENG.EXE
KAVPERS40ENG.EXE
KAVPF.EXE
KAZZA.EXE
KEENVALUE.EXE
KERIO-PF-213-EN-WIN.EXE
KERIO-WRL-421-EN-WIN.EXE
KERIO-WRP-421-EN-WIN.EXE
KERNEL32.EXE
KILLPROCESSSETUP161.EXE
LAUNCHER.EXE
LDNETMON.EXE
LDPRO.EXE
LDPROMENU.EXE
LDSCAN.EXE
LNETINFO.EXE
LOADER.EXE
LOCALNET.EXE
LOCKDOWN.EXE
LOCKDOWN2000.EXE
LOOKOUT.EXE
LORDPE.EXE
LSETUP.EXE
LUALL.EXE
LUALL.EXE
LUAU.EXE
LUCOMSERVER.EXE
LUINIT.EXE
LUSPT.EXE
MAPISVC32.EXE
MCAGENT.EXE
MCMNHDLR.EXE
MCSHIELD.EXE
MCTOOL.EXE
MCUPDATE.EXE
MCUPDATE.EXE
MCVSRTE.EXE
MCVSSHLD.EXE
MD.EXE
MFIN32.EXE
MFW2EN.EXE
MFWENG3.02D30.EXE
MGAVRTCL.EXE
MGAVRTE.EXE
MGHTML.EXE
MGUI.EXE
MINILOG.EXE
MMOD.EXE
MONITOR.EXE
MOOLIVE.EXE
MOSTAT.EXE
MPFAGENT.EXE
MPFSERVICE.EXE
MPFTRAY.EXE
MRFLUX.EXE
MSAPP.EXE
MSBB.EXE
MSBLAST.EXE
MSCACHE.EXE
MSCCN32.EXE
MSCMAN.EXE
MSCONFIG.EXE
MSDM.EXE
MSDOS.EXE
MSIEXEC16.EXE
MSINFO32.EXE
MSLAUGH.EXE
MSMGT.EXE
MSMSGRI32.EXE
MSSMMC32.EXE
MSSYS.EXE
MSVXD.EXE
MU0311AD.EXE
MWATCH.EXE
N32SCANW.EXE
NAV.EXE
AUTO-PROTECT.NAV80TRY.EXE
NAVAP.NAVAPSVC.EXE
NAVAPSVC.EXE
NAVAPW32.EXE
NAVDX.EXE
NAVLU32.EXE
NAVNT.EXE
NAVSTUB.EXE
NAVW32.EXE
NAVWNT.EXE
NC2000.EXE
NCINST4.EXE
NDD32.EXE
NEOMONITOR.EXE
NEOWATCHLOG.EXE
NETARMOR.EXE
NETD32.EXE
NETINFO.EXE
NETMON.EXE
NETSCANPRO.EXE
NETSPYHUNTER-1.2.EXE
NETSTAT.EXE
NETUTILS.EXE
NISSERV.EXE
NISUM.EXE
NMAIN.EXE
NOD32.EXE
NORMIST.EXE
NORTON_INTERNET_SECU_3.0_407.EXE
NOTSTART.EXE
NPF40_TW_98_NT_ME_2K.EXE
NPFMESSENGER.EXE
NPROTECT.EXE
NPSCHECK.EXE
NPSSVC.EXE
NSCHED32.EXE
NSSYS32.EXE
NSTASK32.EXE
NSUPDATE.EXE
NT.EXE
NTRTSCAN.EXE
NTVDM.EXE
NTXconfig.EXE
NUI.EXE
NUPGRADE.EXE
NUPGRADE.EXE
NVARCH16.EXE
NVC95.EXE
NVSVC32.EXE
NWINST4.EXE
NWSERVICE.EXE
NWTOOL16.EXE
OLLYDBG.EXE
ONSRVR.EXE
OPTIMIZE.EXE
OSTRONET.EXE
OTFIX.EXE
OUTPOST.EXE
OUTPOST.EXE
OUTPOSTINSTALL.EXE
OUTPOSTPROINSTALL.EXE
PADMIN.EXE
PANIXK.EXE
PATCH.EXE
PAVCL.EXE
PAVPROXY.EXE
PAVSCHED.EXE
PAVW.EXE
PCFWALLICON.EXE
PCIP10117_0.EXE
PCSCAN.EXE
PDSETUP.EXE
PERISCOPE.EXE
PERSFW.EXE
PERSWF.EXE
PF2.EXE
PFWADMIN.EXE
PGMONITR.EXE
PINGSCAN.EXE
PLATIN.EXE
POP3TRAP.EXE
POPROXY.EXE
POPSCAN.EXE
PORTDETECTIVE.EXE
PORTMONITOR.EXE
POWERSCAN.EXE
PPINUPDT.EXE
PPTBC.EXE
PPVSTOP.EXE
PRIZESURFER.EXE
PRMT.EXE
PRMVR.EXE
PROCDUMP.EXE
PROCESSMONITOR.EXE
PROCEXPLORERV1.0.EXE
PROGRAMAUDITOR.EXE
PROPORT.EXE
PROTECTX.EXE
PSPF.EXE
PURGE.EXE
QCONSOLE.EXE
QSERVER.EXE
RAPAPP.EXE
RAV7.EXE
RAV7WIN.EXE
RAV8WIN32ENG.EXE
RAY.EXE
RB32.EXE
RCSYNC.EXE
REALMON.EXE
REGED.EXE
REGEDIT.EXE
REGEDT32.EXE
RESCUE.EXE
RESCUE32.EXE
RRGUARD.EXE
RSHELL.EXE
RTVSCAN.EXE
RTVSCN95.EXE
RULAUNCH.EXE
RUN32DLL.EXE
RUNDLL.EXE
RUNDLL16.EXE
RUXDLL32.EXE
SAFEWEB.EXE
SAHAGENT.EXE
SAVE.EXE
SAVENOW.EXE
SBSERV.EXE
SC.EXE
SCAM32.EXE
SCAN32.EXE
SCAN95.EXE
SCANPM.EXE
SCRSCAN.EXE
SETUPVAMEEVAL.EXE
SETUP_FLOWPROTECTOR_US.EXE
SFC.EXE
SGSSFW32.EXE
SH.EXE
SHELLSPYINSTALL.EXE
SHN.EXE
SHOWBEHIND.EXE
SMC.EXE
SMS.EXE
SMSS32.EXE
SOAP.EXE
SOFI.EXE
SPERM.EXE
SPF.EXE
SPHINX.EXE
SPOLER.EXE
SPOOLCV.EXE
SPOOLSV32.EXE
SPYXX.EXE
SREXE.EXE
SRNG.EXE
SS3EDIT.EXE
SSGRATE.EXE
SSG_4104.EXE
ST2.EXE
START.EXE
STCLOADER.EXE
SUPFTRL.EXE
SUPPORT.EXE
SUPPORTER5.EXE
SVC.EXE
SVCHOSTC.EXE
SVCHOSTS.EXE
SVSHOST.EXE
SWEEP95.EXE
SWEEPNET.SWEEPSRV.SYS.SWNETSUP.EXE
SYMPROXYSVC.EXE
SYMTRAY.EXE
SYSEDIT.EXE
SYSTEM.EXE
SYSTEM32.EXE
SYSUPD.EXE
TASKMG.EXE
TASKMO.EXE
TASKMON.EXE
TAUMON.EXE
TBSCAN.EXE
TC.EXE
TCA.EXE
TCM.EXE
TDS-3.EXE
TDS2-NT.EXE
TEEKIDS.EXE
TFAK.EXE
TFAK5.EXE
TGBOB.EXE
TITANIN.EXE
TITANINXP.EXE
TRACERT.EXE
TRICKLER.EXE
TRJSCAN.EXE
TRJSETUP.EXE
TROJANTRAP3.EXE
TSADBOT.EXE
TVMD.EXE
TVTMD.EXE
UNDOBOOT.EXE
UPDAT.EXE
UPDATE.EXE
UPDATE.EXE
UPGRAD.EXE
UTPOST.EXE
VBCMSERV.EXE
VBCONS.EXE
VBUST.EXE
VBWIN9X.EXE
VBWINNTW.EXE
VCSETUP.EXE
VET32.EXE
VET95.EXE
VETTRAY.EXE
VFSETUP.EXE
VIR-HELP.EXE
VIRUSMDPERSONALFIREWALL.EXE
VNLAN300.EXE
VNPC3000.EXE
VPC32.EXE
VPC42.EXE
VPFW30S.EXE
VPTRAY.EXE
VSCAN40.EXE
VSCENU6.02D30.EXE
VSCHED.EXE
VSECOMR.EXE
VSHWIN32.EXE
VSISETUP.EXE
VSMAIN.EXE
VSMON.EXE
VSSTAT.EXE
VSWIN9XE.EXE
VSWINNTSE.EXE
VSWINPERSE.EXE
W32DSM89.EXE
W9X.EXE
WATCHDOG.EXE
WEBDAV.EXE
WEBSCANX.EXE
WEBTRAP.EXE
WFINDV32.EXE
WHOSWATCHINGME.EXE
WIMMUN32.EXE
WIN-BUGSFIX.EXE
WIN32.EXE
WIN32US.EXE
WINACTIVE.EXE
WINDOW.EXE
WINDOWS.EXE
WININETD.EXE
WININIT.EXE
WININITX.EXE
WINLOGIN.EXE
WINMAIN.EXE
WINNET.EXE
WINPPR32.EXE
WINRECON.EXE
WINSERVN.EXE
WINSSK32.EXE
WINSTART.EXE
WINSTART001.EXE
WINTSK32.EXE
WINUPDATE.EXE
WKUFIND.EXE
WNAD.EXE
WNT.EXE
WRADMIN.EXE
WRCTRL.EXE
WSBGATE.EXE
WUPDATER.EXE
WUPDT.EXE
WYVERNWORKSFIREWALL.EXE
XPF202EN.EXE
ZAPRO.EXE
ZAPSETUP3001.EXE
ZATUTOR.EXE
ZONALM2601.EXE
ZONEALARM.EXE
_AVP32.EXE
_AVPCC.EXE
_AVPM.EXE
CMD.EXE
TASKMGR.EXE
NEC.EXE
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