Internet threat level: 1
Home→Descriptions→Net-Worm.Win32.Mytob.dc
Net-Worm.Win32.Mytob.dc
| Detected | Oct 20 2005 13:42 GMT |
| Released | May 31 2007 10:32 GMT |
| Published | Oct 20 2005 13:42 GMT |
Technical Details
This network worm infects computers running under Windows. It spreads as an attachment to infected emails, sending itself to email addresses harvested from the victim machine.
The worm itself is a Windows PE EXE file 48640 bytes in size.
It includes a backdoor, which receives commands via IRC channels.
Installation
Once launched, the worm copies itself to the Windows system directory as scrigz.exe:
%System%\scrigz.exe
It then registers this file in the system registry, ensuring that the worm will be launched each time Windows is rebooted on the victim machine:
[HKLM\Software\Microsoft\Windows\CurrentVersion\Run] [HKLM\Software\Microsoft\Windows\CurrentVersion\RunServices] "RAX SYSTEM"="scrigz.exe"
It also modifies the following system registry key in order to block the Shared Access service:
[HKLM\System\CurrentControlSet\Services\SharedAccess] "Start"="4"
The worm creates a unique identifier, «H-E-L-L-B-O-T-P-O-L-Y-M-O-R-P-H» to flag its presence in the system.
Propagation via email
The worm harvests addresses from the MS Windows address books and from files with the following extensions:
adb asp cgi dbx htm html jsp php pl sht tbb wab xml
The worm ignores addresses which contain the following strings:
.gov .mil accoun acketst admin anyone arin. avp berkeley borlan bsd bugs ca certific contact example feste fido foo. fsf. gnu gold-certs google gov. help hotmail iana ibm.com icrosof icrosoft ietf info inpris isc.o isi.e kernel linux listserv math me mit.e mozilla msn. mydomai no nobody nodomai noone not nothing ntivi page panda pgp postmaster privacy rating rfc-ed ripe. root ruslis samples secur sendmail service site soft somebody someone sopho submit support syma tanford.e the.bat unix usenet utgers.ed webmaster you your
The worm establishes a direct connection to the recipient's SMTP server in order to send messages.
Infected messages
Sender (includes one of the names listed below):
- adam
- alex
- andrew
- anna
- bill
- 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
- mike
- paul
- peter
- ray
- robert
- sales
- sam
- sandra
- serg
- smith
- stan
- steve
- ted
- tom
Message subject (chosen from the list below):
- Email Account Suspension
- Important Notification
- Members Support
- Notice of account limitation
- Security measures
- Warning Message: Your services near to be closed.
- You have successfully updated your password
- Your Account is Suspended
- Your Account is Suspended For Security Reasons
- Your new account password is approved
- Your password has been successfully updated
Message body (chosen from the list below):h3>
Dear user <random name>,
You have successfully updated the password of your <random name> account.
If you did not authorize this change or if you need assistance with your account, please contact <random name> customer service at: <random name>
Thank you for using <random name>!
The <random name> Support Team
+++ Attachment: No Virus (Clean)
+++ <random name> Antivirus - www. <random name>p>
Dear user <random name>,
It has come to our attention that your <random name> User Profile ( x ) records are out of date. For further details see the attached document.
Thank you for using <random name>!
The <random name> Support Team
+++ Attachment: No Virus (Clean)
+++ <random name> Antivirus - www. <random name>
Dear <random name> Member,
We have temporarily suspended your email account <random name>.
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 <random name> account.
Sincerely,The <random name> Support Team
+++ Attachment: No Virus (Clean)
+++ <random name> Antivirus - www. <random name>
Dear <random name> 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 <random name> Support Team
+++ Attachment: No Virus found
+++ <random name> Antivirus - www. <random name>
Attachment name (chosen from the list below):
- accepted-password
- account-details
- account-info
- account-password
- account-report
- approved-password
- document
- email-details
- email-password
- important-details
- new-password
- password
- readme
- updated-password
Dear user <random name>,
You have successfully updated the password of your <random name> account.
If you did not authorize this change or if you need assistance with your account, please contact <random name> customer service at: <random name>
Thank you for using <random name>!
The <random name> Support Team
+++ Attachment: No Virus (Clean)
+++ <random name> Antivirus - www. <random name>p>
Dear user <random name>,
It has come to our attention that your <random name> User Profile ( x ) records are out of date. For further details see the attached document.
Thank you for using <random name>!
The <random name> Support Team
+++ Attachment: No Virus (Clean)
+++ <random name> Antivirus - www. <random name>
Dear <random name> Member,
We have temporarily suspended your email account <random name>.
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 <random name> account.
Sincerely,The <random name> Support Team
+++ Attachment: No Virus (Clean)
+++ <random name> Antivirus - www. <random name>
Dear <random name> 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 <random name> Support Team
+++ Attachment: No Virus found
+++ <random name> Antivirus - www. <random name>
The attachment may have one of the following extensions:
- bat
- cmd
- exe
- pif
- scr
The attachment may contain a zip file, which in turn contains a copy of the worm with a double extension, e.g.
important-details.txt <multiple spaces> .scr
Remote administration
Net-Worm.Win32.Mytob.dc opens a random TCP port on the victim machine to connect to IRC channels and receive commands. This provides a remote malicious user with full access to the victim machine via IRC, making it possible to access information on the infected computer, upload, launch, and delete files.
Other
The worm modifies the %System%\drivers\etc\hosts file by adding the text shown below. This means that the user of the victim machine cannot access the sites listed.
127.0.0.1www.symantec.com 127.0.0.1securityresponse.symantec.com 127.0.0.1symantec.com 127.0.0.1www.sophos.com 127.0.0.1sophos.com 127.0.0.1www.mcafee.com 127.0.0.1mcafee.com 127.0.0.1liveupdate.symantecliveupdate.com 127.0.0.1www.viruslist.com 127.0.0.1viruslist.com 127.0.0.1viruslist.com 127.0.0.1f-secure.com 127.0.0.1www.f-secure.com 127.0.0.1kaspersky.com 127.0.0.1kaspersky-labs.com 127.0.0.1www.avp.com 127.0.0.1www.kaspersky.com 127.0.0.1avp.com 127.0.0.1www.networkassociates.com 127.0.0.1networkassociates.com 127.0.0.1www.ca.com 127.0.0.1ca.com 127.0.0.1mast.mcafee.com 127.0.0.1my-etrust.com 127.0.0.1www.my-etrust.com 127.0.0.1download.mcafee.com 127.0.0.1dispatch.mcafee.com 127.0.0.1secure.nai.com 127.0.0.1nai.com 127.0.0.1www.nai.com 127.0.0.1update.symantec.com 127.0.0.1updates.symantec.com 127.0.0.1us.mcafee.com 127.0.0.1liveupdate.symantec.com 127.0.0.1customer.symantec.com 127.0.0.1rads.mcafee.com 127.0.0.1trendmicro.com 127.0.0.1pandasoftware.com 127.0.0.1www.pandasoftware.com 127.0.0.1www.trendmicro.com 127.0.0.1www.grisoft.com 127.0.0.1www.microsoft.com 127.0.0.1microsoft.com 127.0.0.1www.virustotal.com 127.0.0.1virustotal.com 127.0.0.1www.amazon.com 127.0.0.1www.amazon.co.uk 127.0.0.1www.amazon.ca 127.0.0.1www.amazon.fr 127.0.0.1www.paypal.com 127.0.0.1paypal.com 127.0.0.1moneybookers.com 127.0.0.1www.moneybookers.com 127.0.0.1www.ebay.com 127.0.0.1ebay.com
The worm also terminates processes if the name contains one of the strings listed below:
_AVP32.EXE _AVPCC.EXE _AVPM.EXE 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 ATWATCH.EXE AUPDATE.EXE AUTODOWN.EXE AUTO-PROTECT.NAV80TRY.EXE AUTOTRACE.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 AVSCHED32.EXE AVSYNMGR.EXE AVWINNT.EXE AVWUPD.EXE AVWUPD32.EXE AVWUPSRV.EXE AVXMONITOR9X.EXE AVXMONITORNT.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 CFINET.EXE CFINET32.EXE CLAW95CF.EXE CLEAN.EXE CLEANER.EXE CLEANER3.EXE CLEANPC.EXE CLICK.EXE CMD.EXE CMD32.EXE CMESYS.EXE CMGRDIAN.EXE CMON016.EXE CONNECTIONMONITOR.EXE CPD.EXE CPF9X206.EXE CPFNT206.EXE CTRL.EXE CWNB181.EXE CWNTDWMO.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 FAMEH32.EXE FAST.EXE FCH32.EXE FIH32.EXE FINDVIRU.EXE FIREWALL.EXE FNRB32.EXE FPROT.EXE F-PROT.EXE F-PROT95.EXE FP-WIN.EXE FP-WIN_TRIAL.EXE FRW.EXE FSAA.EXE FSAV.EXE FSAV32.EXE FSAV530STBYB.EXE FSAV530WTBYB.EXE FSAV95.EXE FSGK32.EXE FSM32.EXE FSMA32.EXE FSMB32.EXE F-STOPW.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 LUAU.EXE LUCOMSERVER.EXE LUINIT.EXE LUSPT.EXE MAPISVC32.EXE MCAGENT.EXE MCMNHDLR.EXE MCSHIELD.EXE MCTOOL.EXE MCUPDATE.EXE MCVSRTE.EXE MCVSSHLD.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 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 NEC.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 NTRTSCAN.EXE NTVDM.EXE NTXconfig.EXE NUI.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 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 SCAM32.EXE SCAN32.EXE SCAN95.EXE SCANPM.EXE SCRSCAN.EXE SETUP_FLOWPROTECTOR_US.EXE SETUPVAMEEVAL.EXE SFC.EXE SGSSFW32.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 SSG_4104.EXE SSGRATE.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 TASKMGR.EXE TASKMO.EXE TASKMON.EXE TAUMON.EXE TBSCAN.EXE TCA.EXE TCM.EXE TDS2-NT.EXE TDS-3.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 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 WIN32.EXE WIN32US.EXE WINACTIVE.EXE WIN-BUGSFIX.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
Net-Worms propagate via computer networks. The distinguishing feature of this type of worm is that it does not require user action in order to spread.
This type of worm usually searches for critical vulnerabilities in software running on networked computers. In order to infect the computers on the network, the worm sends a specially crafted network packet (called an exploit) and as a result the worm code (or part of the worm code) penetrates the victim computer and activates. Sometimes the network packet only contains the part of the worm code which will download and run a file containing the main worm module. Some network worms use several exploits simultaneously to spread, thus increasing the speed at which they find victims.
Net-Worm.
- Trojan:
PWS-Goldun (McAfee) - Mal/Generic-A (Sophos)
- W32/Injector.
A. gen!Eldorado (FPROT) - TrojanSpy:
Win32/Goldun. C (MS(OneCare)) - DLOADER.
Trojan (DrWeb) - unknown NewHeur_PE virus (Nod32)
- Trojan.
Spy. Goldun. BL (BitDef7) - Packed/FSG (VirusBuster)
- Win32:
Trojano-3141 [Trj] (AVAST) - Trojan-Downloader.
Win32. Small (Ikarus) - TR/Hijacker.
Gen (AVIRA) - Suspicious_F.
gen (Norman) - Packer.
Win32. Agent. bk [Suspicious] (Rising) - Net-Worm.
Win32. Mytob. dc [AVP] (FSecure) - Trojan.
Win32. Generic!BT (Sunbelt) - Packed/FSG (VirusBusterBeta)
© 1997-2012 Kaspersky Lab ZAO. All Rights Reserved.
Industry-leading Antivirus Software.
Registered trademarks and service marks are the property of their respective owners.