WORM_MYTOB.HU

Malware type: Worm

Aliases: Net-Worm.Win32.Mytob.bi (Kaspersky), W32.Mytob@mm (Symantec), Worm/Mytob.JF (Avira), W32/Mytob-HU (Sophos),

In the wild: Yes

Destructive: No

Language: English

Platform: Windows 98, ME, NT, 2000, XP

Encrypted: No

Overall risk rating:

Reported infections:

Damage potential:

High

Distribution potential:

High

Description: 

Similar to other MYTOB variants, this memory-resident worm propagates by sending a copy of itself as an attachment to an email message, which it sends to target recipients using its own Simple Mail Transfer Protocol (SMTP) engine.

This email message has the following details:

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

Message body: (any of the following)
---
Dear user {random},

You have successfully updated the password of your {random} account.
If you did not authorize this change or if you need assistance with your account, please contact {random} customer service at: {random}

Thank you for using {random}!
The {random} Support Team

%20%20%20 Attachment: No Virus (Clean)
%20%20%20 {random} Antivirus - {random URL}

---
Dear user {random},

It has come to our attention that your {random} User Profile ( x ) records are out of date. For further details see the attached document.

Thank you for using {random}!
The {random} Support Team

%20%20%20 Attachment: No Virus (Clean)
%20%20%20 {random} Antivirus - {random URL}

---
Dear {random} Member,

We have temporarily suspended your email account {random}.
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} account.

Sincerely,
The {random} Support Team

%20%20%20 Attachment: No Virus (Clean)
%20%20%20 {random} Antivirus - {random URL}

---
Dear {random} 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} Support Team

%20%20%20 Attachment: No Virus found
%20%20%20 {random} Antivirus - {random URL}

Attachment: (A .ZIP file that contains a copy of itself with any combination of the following file names and extensions:)

File name:
account-details
account-info
account-report
document
email-details
important-details
readme

Extension:
DOC
HTM
TMP
TXT

Note: The file name extension of the archived file is followed by empty spaces, a dot, and any of the following extensions:
EXE
PIF
SCR

Below is a sample screenshot of the message it sends out:

It gathers target email addresses from the Windows Address Book (WAB), as well as from files with certain extension names. It may also generate email addresses by using a list of names and any of the domain names of the previously gathered addresses.

It also has backdoor capabilities. It opens a random port, which allows a remote user to perform malicious commands on the affected machine. The said routine provides remote users virtual control over affected systems, thus compromising system security.

This worm is capable of preventing users from accessing several antivirus and security Web sites by modifying the HOSTS file. As a result, it redirects the connection to the local machine. It also terminates several processes running on the affected system.

For additional information about this threat, see:

Description created: Jul. 27, 2005 3:49:29 AM GMT -0800


TECHNICAL DETAILS


File type: PE

Memory resident:  Yes

Size of malware: 36,352 Bytes

Initial samples received on: Jul 27, 2005

Payload 1: Performs backdoor routines

Payload 2: Modifies HOSTS file

Payload 3: Terminates processes

Details:

Installation and Autostart Techniques

This memory-resident worm may arrive on a system as an email attachment. Upon execution, it drops a copy of itself in the Windows system folder as the file GOTHICA.EXE.

It then creates the following registry entries to enable its automatic execution at every Windows startup:

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\CurrentVersion\Run
WINDOWS SYSTEM = "gothica.exe"

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\CurrentVersion\RunServices
WINDOWS SYSTEM = "gothica.exe"

It also modifies the following registry entry to lower the affected system's security settings:

From

HKEY_LOCAL_MACHINE\System\CurrentControlSet\
Services\SharedAccess
Start = "00000003"

To

HKEY_LOCAL_MACHINE\System\CurrentControlSet\
Services\SharedAccess
Start = "00000004"

Email Propagation

This worm propagates by sending a copy of itself as an attachment to email messages, which it then sends to target addresses using its own Simple Mail Transfer Protocol (SMTP) engine.

It also checks the following registry key for any available SMTP server that it can use to propagate further:

HKEY_CURRENT_USER\Software\Microsoft\
Internet Account Manager\Accounts

The email message it sends out contains the following details:

Subject: (any of the following)
� *DETECTED* Online User Violation
� Email Account Suspension
� Important Notification
� Members Support
� Notice of account limitation
� Security measures
� Warning Message: Your services near to be closed.
� Your Account is Suspended
� Your Account is Suspended For Security Reasons

Message body: (any of the following)
---
Dear user {random},

You have successfully updated the password of your {random} account.
If you did not authorize this change or if you need assistance with your account, please contact {random} customer service at: {random}

Thank you for using {random}!
The {random} Support Team

%20%20%20 Attachment: No Virus (Clean)
%20%20%20 {random} Antivirus - {random URL}

---
Dear user {random},

It has come to our attention that your {random} User Profile ( x ) records are out of date. For further details see the attached document.

Thank you for using {random}!
The {random} Support Team

%20%20%20 Attachment: No Virus (Clean)
%20%20%20 {random} Antivirus - {random URL}

---
Dear {random} Member,

We have temporarily suspended your email account {random}.
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} account.

Sincerely,
The {random} Support Team

%20%20%20 Attachment: No Virus (Clean)
%20%20%20 {random} Antivirus - {random URL}

---
Dear {random} 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} Support Team

%20%20%20 Attachment: No Virus found
%20%20%20 {random} Antivirus - {random URL}

Attachment: (A .ZIP file that contains a copy of itself with any combination of the following file names and extensions:)

File name:
� account-details
� account-info
� account-report
� document
� email-details
� important-details
� readme

Extension:
� DOC
� HTM
� TMP
� TXT

Note: The file name extension of the archived file is followed by empty spaces, a dot, and any of the following extensions:
� EXE
� PIF
� SCR

Below is a sample screenshot of the message it sends out:

This worm gathers target email addresses from the the Windows Address Book (WAB). It does the said routine by checking the following registry key:

HKEY_LOCAL_MACHINE\Software\Microsoft\
WAB\WAB4\Wab File Name

If a default mail server is not found, it queries the message exchange servers of gathered email addresses by appending the domain names with the following strings:

  • gate.
  • mail.
  • mail1.
  • mx.
  • mx1.
  • mxs.
  • ns.
  • relay.
  • smtp.

It may also generate email addresses by combining the following names with a domain name copied from harvested addresses in the WAB:

  • andrew
  • brenda
  • brent
  • brian
  • claudia
  • david
  • debby
  • frank
  • george
  • helen
  • james
  • jerry
  • jimmy
  • julie
  • kevin
  • linda
  • maria
  • michael
  • peter
  • robert
  • sales
  • sandra
  • smith
  • steve

This worm also gathers email addresses from files with any of the following extension names:

  • ADBH
  • ASPD
  • CGIL
  • DBXN
  • HTM
  • HTML
  • JSPL
  • PHPQ
  • PL
  • SHTL
  • TBBG
  • TXT
  • WAB
  • XMLS

Notably, it avoids sending messages to email addresses that contain any of the following strings:

  • acketst
  • arin.
  • be_loyal:
  • berkeley
  • borlan
  • example
  • google
  • ibm.com
  • icrosof
  • inpris
  • isc.o
  • isi.e
  • kernel
  • linux
  • mit.e
  • mozilla
  • mydomai
  • nodomai
  • panda
  • postmaster
  • rfc-ed
  • ripe.
  • ruslis
  • samples
  • secur
  • sendmail
  • sopho
  • tanford.e
  • usenet
  • utgers.ed
  • webmaster

Backdoor Capabilities

This worm also has backdoor capabilities. It connects to the IRC server irc.wargamesecurity.com and joins the channel #.MaKaVeLi's-StaSh.#, where it receives the following commands from a remote malicious user:

  • Download and execute files
  • Obtain system information
  • Remove/Update this bot
  • Start/Terminate its mass-mailing routine

HOSTS File Modification

This worm also modifies the system's HOSTS file, which associates the host name to IP address mappings. It is usually located in the following folders:

  • %System%\drivers\etc
  • %Windows%
(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 95, 98, and ME, C:\WINNT\System32 on Windows NT and 2000, and C:\Windows\System32 on Windows XP and Server 2003. %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.)

It appends a list of Web site addresses and directs them to the loopback address (127.0.0.1). This prevents the user from accessing the specified locations. Instead, the user is redirected to the local Web site of the infected machine.

The said routine is done so that the following sites, which are usually related to antivirus companies, can no longer be accessed by affected users:

  • avp.com
  • ca.com
  • customer.symantec.com
  • dispatch.mcafee.com
  • download.mcafee.com
  • f-secure.com
  • kaspersky-labs.com
  • kaspersky.com
  • liveupdate.symantec.com
  • liveupdate.symantecliveupdate.com
  • mast.mcafee.com
  • mcafee.com
  • microsoft.com
  • my-etrust.com
  • nai.com
  • networkassociates.com
  • pandasoftware.com
  • rads.mcafee.com
  • secure.nai.com
  • securityresponse.symantec.com
  • sophos.com
  • symantec.com
  • trendmicro.com
  • update.symantec.com
  • updates.symantec.com
  • us.mcafee.com
  • viruslist.com
  • virustotal.com
  • www.avp.com
  • www.ca.com
  • www.f-secure.com
  • www.grisoft.com
  • www.kaspersky.com
  • www.mcafee.com
  • www.microsoft.com
  • www.my-etrust.com
  • www.nai.com
  • www.networkassociates.com
  • www.pandasoftware.com
  • www.sophos.com
  • www.symantec.com
  • www.trendmicro.com
  • www.viruslist.com
  • www.virustotal.com

Process Termination

This worm terminates the following processes, some of which are related to antivirus and security programs:

  • _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
  • AU.EXE
  • AUPDATE.EXE
  • AUTO-PROTECT.NAV80TRY.EXE
  • AUTODOWN.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
  • CV.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
  • 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
  • LUAU.EXE
  • LUCOMSERVER.EXE
  • LUINIT.EXE
  • LUSPT.EXE
  • MAPISVC32.EXE
  • MCAGENT.EXE
  • MCMNHDLR.EXE
  • MCSHIELD.EXE
  • MCTOOL.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
  • 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
  • NT.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
  • SC.EXE
  • SCAM32.EXE
  • SCAN32.EXE
  • SCAN95.EXE
  • SCANPM.EXE
  • SCRSCAN.EXE
  • SETUP_FLOWPROTECTOR_US.EXE
  • SETUPVAMEEVAL.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
  • 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
  • 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
  • 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

Other Details

This worm creates the mutex H-E-L-L-B-O-T-P-O-L-Y-M-O-R-P-H to ensure that only one instance of itself is running in memory.

It runs on Windows 98, ME, NT, 2000, and XP.

Analysis By: Marco A dela Vega


SOLUTION


Minimum scan engine version needed: 6.810

Pattern file needed: 2.748.04

Pattern release date: Jul 27, 2005


Important note: The "Minimum scan engine" refers to the earliest Trend Micro scan engine version guaranteed to detect this threat. However, Trend Micro strongly recommends that you update to the latest version in order to get comprehensive protection. Download the latest scan engine here.

Solution:

Identifying the Malware Program

To remove this malware, first identify the malware program.

  1. Scan your system with your Trend Micro antivirus product.
  2. NOTE all files detected as WORM_MYTOB.HU.

Trend Micro customers need to download the latest pattern file before scanning their system. Other users can use Housecall, Trend Micro's online virus scanner.

Terminating the Malware Program

Since this malware terminates the Windows Task Manager, it is necessary to use third party process viewers such as Process Explorer. You will need the name(s) of the file(s) detected earlier.

  1. Download Process Explorer.
  2. Extract the contents of the compressed (ZIP) file to a location of your choice.
  3. Execute Process Explorer by double-clicking procexp.exe.
  4. In the Process Explorer window, locate the malware file(s) detected earlier.
  5. Right-click one of the detected files, then click Kill Process Tree.
  6. Do the same for all detected malware files in the list of running processes.
  7. Close Process Explorer.

Editing the Registry

This malware modifies the system's registry. Users affected by this malware may need to modify or delete specific registry keys or entries. For detailed information regarding registry editing, please refer to the following articles from Microsoft:

  1. HOW TO: Backup, Edit, and Restore the Registry in Windows 95, Windows 98, and Windows ME
  2. HOW TO: Backup, Edit, and Restore the Registry in Windows NT 4.0
  3. HOW TO: Backup, Edit, and Restore the Registry in Windows 2000
  4. HOW TO: Back Up, Edit, and Restore the Registry in Windows XP and 2003

Removing Autostart Entries from the Registry

Removing autostart entries from the registry prevents the malware from executing at startup.

If the registry entries below are not found, the malware may not have executed as of detection. If so, proceed to the succeeding solution set.

  1. Open Registry Editor. Click Start>Run, type REGEDIT, then press Enter.
  2. In the left panel, double-click the following:
    HKEY_LOCAL_MACHINE>Software>Microsoft>
    Windows>CurrentVersion>Run
  3. In the right panel, locate and delete the entry:
    WINDOWS SYSTEM = "gothica.exe"
  4. In the left panel, double-click the following:
    HKEY_LOCAL_MACHINE>Software>Microsoft>
    Windows>CurrentVersion>RunServices
  5. In the right panel, locate and delete the entry:
    WINDOWS SYSTEM = "gothica.exe"

Restoring Registry Modifications

  1. Still in the Registry Editor, in the left panel, double-click the following:
    HKEY_LOCAL_MACHINE>System>CurrentControlSet>
    Services>SharedAccess
  2. In the right panel, locate the entry:
    Start = "00000004"
    and change this to the following value:
    Start = "00000003"
  3. Close the Registry Editor.

Removing Malware Entries from the HOSTS File

Deleting malware entries from the HOSTS file removes all malware-made changes on host name association.

  1. Open the following file using a text editor (such as NOTEPAD):
    • On Windows 98 and ME:
      %Windows%\HOSTS
    • On Windows NT, 2000, and XP:
      %System%\drivers\etc\HOSTS
    (Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 95, 98, and ME, C:\WINNT\System32 on Windows NT and 2000, and C:\Windows\System32 on Windows XP and Server 2003. %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.)
  2. Delete the following entries:
    • 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
  3. Save the file and close the text editor.

Important Windows ME/XP Cleaning Instructions

Users running Windows ME and XP must disable System Restore to allow full scanning of infected systems.

Users running other Windows versions can proceed with the succeeding procedure set(s).

Running Trend Micro Antivirus

Scan your system with Trend Micro antivirus and delete files detected as WORM_MYTOB.HU. To do this, Trend Micro customers must download the latest pattern file and scan their system. Other Internet users can use HouseCall, Trend Micro's online virus scanner.




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