WORM_MYTOB.QR

Malware type: Worm

Aliases: No Alias Found

In the wild: Yes

Destructive: No

Language: English

Platform: Windows 98, ME, NT, 2000, XP, Server 2003

Encrypted: No

Overall risk rating:

Reported infections:

Damage potential:

High

Distribution potential:

High

Infection Channel 1 : Propagates via peer-to-peer networks


Infection Channel 2 : Propagates via removable drives


Infection Channel 3 : Spammed via email


Description: 

To get a one-glance comprehensive view of the behavior of this malware, refer to the Behavior Diagram shown below.

WORM_MYTOB.QR Behavior Diagram

Malware Overview

This worm arrives as attachment to mass-mailed email messages. It may also arrive via removable drives.

It drops multiple files on the affected system, including copies of itself and possibly malicious component files.

It displays an image when executed.

It creates a registry entry to enable its automatic execution at every system startup.

It uses its own Simple Mail Transfer Protocol (SMTP) engine to send email messages with a copy of itself as attachment. It gathers target email addresses from the Windows Address Book (WAB).

It may also generate target email addresses by using common names, appended with a domain name that it copies from previously gathered addresses, or from a list found in its code. However, it avoids sending email messages to addresses containing certain strings.

It obtains an SMTP server by querying for various external servers on the various target domains.

It drops copies of itself in folders used in peer-to-peer networks. It also drops copies of itself in all removable drives.

It modifies the system's HOSTS files to prevent users from accessing certain Web sites.

For additional information about this threat, see:

Description created: Jan. 11, 2009 6:30:05 PM GMT -0800


TECHNICAL DETAILS


File type: PE

Memory resident:  Yes

Size of malware: Varies

Initial samples received on: Jan 11, 2009

Payload 1: Modifies HOSTS file

Payload 2: Displays windows

Details:

Arrival, Installation, and Autostart Techniques

This worm arrives as attachment to mass-mailed email messages. It may also arrive via removable drives.

This worm drops the following copy of itself:

  • %System%\javaw.exe

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

If the said file is already present on the affected system, the original file is overwritten by the malware.

It drops the following component files:

  • %System%\mf.exe - also detected by Trend Micro as WORM_MYTOB.QR
  • %System%\wvUMfFVM.dll
  • %System%\wvUmmKCr.dll

It displays the following image:

This worm creates the following registry entry to enable its automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\
CurrentVersion\Run
SunJavaUpdater = "%System%\javaw.exe"

Propagation via Email

This worm uses its own Simple Mail Transfer Protocol (SMTP) engine to send email messages with a copy of itself as attachment. The email messages it sends out bear the following details:

SUBJECT: You've received A Hallmark E-Card!
BODY: Hallmark.com | Privacy & Security | Customer Service | Store Locator
ATTACHMENT:
FILENAME: postcard.zip
EXTENSION NAME: - First: .zip

It gathers target email addresses from the Windows Address Book (WAB).

It may also generate target email addresses by using the following common names, appended with a domain name that it copies from previously gathered addresses, or from a list found in its code:

  • andre
  • anthony_johnso
  • comercial
  • dkuhlen
  • james
  • john
  • julien
  • karl
  • mapathak
  • mark
  • markus
  • matt_thorn
  • matt_thornton
  • mykaul
  • peter
  • timo.metsala

It avoids sending email messages to addresses containing the following strings:

  • accoun
  • acd-group
  • acdnet.com
  • acdsystems.com
  • acketst
  • admin
  • alcatel-lucent.com
  • anyone
  • apache
  • arin.
  • avira
  • bitdefender
  • bluewin.ch
  • borlan
  • bpsoft.com
  • buyrar.com
  • certific
  • clamav
  • contact
  • drweb
  • eset.com
  • example
  • f-secure
  • feste
  • firefox
  • ghisler.com
  • gold-certs
  • honeynet
  • honeypot
  • icrosof
  • icrosoft
  • idefense
  • ikarus
  • inpris
  • isc.o
  • isi.e
  • jgsoft
  • kaspersky
  • kernel
  • lavasoft
  • linux
  • listserv
  • mcafee
  • messagelabs
  • mozilla
  • mydomai
  • nobody
  • nodomai
  • noone
  • nothing
  • ntivi
  • panda
  • postmaster
  • prevx
  • privacy
  • qualys
  • quebecor.com
  • rating
  • redhat
  • rfc-ed
  • ruslis
  • samples
  • secur
  • security
  • sendmail
  • service
  • slashdot
  • somebody
  • someone
  • sopho
  • sourceforge
  • submit
  • sun.com
  • support
  • syman
  • tanford.e
  • the.bat
  • usenet
  • utgers.ed
  • virusbuster
  • webmaster
  • wireshark
  • www.ca.com

It obtains an SMTP server by querying for the following subdomains at the target domain names:

  • gate
  • mail
  • mail1
  • mx1
  • mxs
  • relay
  • smtp

Propagation via Peer-to-peer Networks

This worm drops copies of itself in the following folders, which are used in peer-to-peer networks:

  • %Program Files%\emule\incoming
  • %Program Files%\grokster
  • %Program Files%\icq\shared folder
  • %Program Files%\limewire\shared\
  • %Program Files%\morpheus\my shared folde
  • %Program Files%\tesla\files\
  • %System Root%\Downloads

(Note: %Program Files% is the default Program Files folder, usually C:\Program Files. %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)

Propagation via Removable Drives

This worm drops copies of itself in all removable drives. It also drops an AUTORUN.INF file to automatically run the said dropped copy.

The dropped AUTORUN.INF file contains the following strings:

[autorun]
open=RECYCLER\S-1-6-21-2434476531-1645641927-102000330-1542\redmond.exe
icon=%SystemRoot%\system32\SHELL32.dll
action=Open Folder to view files
shell\open=open
shell\open\command=RECYCLER\S-1-6-21-2434476531-1645641927-102000330-1542\redmond.exe
shell\open\default=1

HOSTS File Modification

This worm modifies the system's HOSTS file to prevent users from accessing the following Web sites:

  • aladdin.com
  • authentium.com
  • avast.com
  • avg.com
  • avp.com
  • bitdefender.com
  • ca.com
  • customer.symantec.com
  • dispatch.mcafee.com
  • download.mcafee.com
  • eset.com
  • ewido.com
  • f-secure.com
  • free-av.com
  • global.ahnlab.com
  • grisoft.com
  • hispasec.com
  • ikarus-software.at
  • kaspersky-labs.com
  • kaspersky.com
  • liveupdate.symantec.com
  • liveupdate.symantecliveupdate.com
  • mast.mcafee.com
  • mcafee.com
  • my-etrust.com
  • nai.com
  • networkassociates.com
  • pandasecurity.com
  • quickheal.com
  • securityresponse.symantec.com
  • sophos.com
  • symantec.com
  • trendmicro.com
  • update.aladdin.com
  • update.authentium.com
  • update.avast.com
  • update.avg.com
  • update.avp.com
  • update.bitdefender.com
  • update.ca.com
  • update.customer.symantec.com
  • update.dispatch.mcafee.com
  • update.download.mcafee.com
  • update.eset.com
  • update.ewido.com
  • update.f-secure.com
  • update.free-av.com
  • update.global.ahnlab.com
  • update.grisoft.com
  • update.hispasec.com
  • update.ikarus-software.at
  • update.kaspersky-labs.com
  • update.kaspersky.com
  • update.liveupdate.symantec.com
  • update.liveupdate.symantecliveupdate.com
  • update.mast.mcafee.com
  • update.mcafee.com
  • update.my-etrust.com
  • update.nai.com
  • update.networkassociates.com
  • update.pandasecurity.com
  • update.quickheal.com
  • update.securityresponse.symantec.com
  • update.sophos.com
  • update.symantec.com
  • update.trendmicro.com
  • update.us.mcafee.com
  • update.virus-buster.com
  • update.viruslist.com
  • update.virustotal.com
  • us.mcafee.com
  • virus-buster.com
  • viruslist.com
  • virustotal.com
  • www.aladdin.com
  • www.authentium.com
  • www.avast.com
  • www.avg.com
  • www.avp.com
  • www.bitdefender.com
  • www.ca.com
  • www.customer.symantec.com
  • www.dispatch.mcafee.com
  • www.download.mcafee.com
  • www.eset.com
  • www.ewido.com
  • www.f-secure.com
  • www.free-av.com
  • www.global.ahnlab.com
  • www.grisoft.com
  • www.hispasec.com
  • www.ikarus-software.at
  • www.kaspersky-labs.com
  • www.kaspersky.com
  • www.liveupdate.symantec.com
  • www.liveupdate.symantecliveupdate.com
  • www.mast.mcafee.com
  • www.mcafee.com
  • www.my-etrust.com
  • www.nai.com
  • www.networkassociates.com
  • www.pandasecurity.com
  • www.quickheal.com
  • www.securityresponse.symantec.com
  • www.sophos.com
  • www.symantec.com
  • www.trendmicro.com
  • www.us.mcafee.com
  • www.virus-buster.com
  • www.viruslist.com
  • www.virustotal.com

Affected Platforms

This worm runs on Windows 98, ME, NT, 2000, XP, Server 2003.


Analysis By: Emmanuel Alma

Revision History:

First pattern file version: 7.350.08
First pattern file release date: Jul 30, 2010

SOLUTION


Minimum scan engine version needed: 8.700

Pattern file needed: 7.351.00

Pattern release date: Jul 30, 2010


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 Files

  1. Scan your computer with your Trend Micro antivirus product.
  2. Note the path and file name of all files detected as WORM_MYTOB.QR.

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

Terminating the Malware Process

This procedure terminates the running malware process. You will need the name(s) of the file(s) detected earlier.

  1. Open Windows Task Manager.
    • On Windows 98 and ME, press
    CTRL%20ALT%20DELETE
    • On Windows NT, 2000, XP, and Server 2003, press
    CTRL%20SHIFT%20ESC, then click the Processes tab.
  2. In the list of running programs*, locate the malware file(s) detected earlier.
  3. Select one of the detected files, then press either the End Task or the End Process button, depending on the version of Windows on your computer.
  4. Do the same for all detected malware files in the list of running processes.
  5. To check if the malware process has been terminated, close Task Manager, and then open it again.
  6. Close Task Manager.

*NOTE: On computers running Windows 98 and ME, Windows Task Manager may not show certain processes. You can use a third party process viewer such as Process Explorer to terminate the malware process.

If the process you are looking for is not in the list displayed by Task Manager or Process Explorer, continue with the next solution procedure. If the malware process is in the list displayed by either Task Manager or Process Explorer, but you are unable to terminate it, restart your computer in safe mode.

Removing Autostart Entry from the Registry

This solution deletes aregistry entry added by this malware. Before performing the steps below, make sure you know how to back up the registry and how to restore it if a problem occurs. Refer to this Microsoft article for more information about modifying your computer's registry.

  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:
    SunJavaUpdater = "%System%\javaw.exe"
    (Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)
  4. Close Registry Editor.

Deleting the Malware File(s)

  1. Right-click Start then click Search... or Find..., depending on the version of Windows you are running.
  2. In the Named input box, type:
    %System%\mf.exe
  3. In the Look In drop-down list, select the drive that contains Windows, then press Enter.
  4. Once located, select the file then press SHIFT%20DELETE.
  5. Repeat steps 2-4 for the following file(s):
    • %System%\wvUMfFVM.dll
    • %System%\wvUmmKCr.dll

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.SAM
    (Note: %Windows% is the Windows folder, which is usually C:\Windows.)
    • On Windows NT, 2000, XP, and Server 2003:
      %System%\drivers\etc\HOSTS
    (Note: %System% is the Windows system folder, which is usually C:\WINNT\System32 on Windows NT and 2000, and C:\Windows\System32 on Windows XP and Server 2003.)
  2. Delete the following entries:
    • 127.0.0.1 aladdin.com
    • 127.0.0.1 authentium.com
    • 127.0.0.1 avast.com
    • 127.0.0.1 avg.com
    • 127.0.0.1 avp.com
    • 127.0.0.1 bitdefender.com
    • 127.0.0.1 ca.com
    • 127.0.0.1 customer.symantec.com
    • 127.0.0.1 dispatch.mcafee.com
    • 127.0.0.1 download.mcafee.com
    • 127.0.0.1 eset.com
    • 127.0.0.1 ewido.com
    • 127.0.0.1 f-secure.com
    • 127.0.0.1 free-av.com
    • 127.0.0.1 global.ahnlab.com
    • 127.0.0.1 grisoft.com
    • 127.0.0.1 hispasec.com
    • 127.0.0.1 ikarus-software.at
    • 127.0.0.1 kaspersky-labs.com
    • 127.0.0.1 kaspersky.com
    • 127.0.0.1 liveupdate.symantec.com
    • 127.0.0.1 liveupdate.symantecliveupdate.com
    • 127.0.0.1 mast.mcafee.com
    • 127.0.0.1 mcafee.com
    • 127.0.0.1 my-etrust.com
    • 127.0.0.1 nai.com
    • 127.0.0.1 networkassociates.com
    • 127.0.0.1 pandasecurity.com
    • 127.0.0.1 quickheal.com
    • 127.0.0.1 securityresponse.symantec.com
    • 127.0.0.1 sophos.com
    • 127.0.0.1 symantec.com
    • 127.0.0.1 trendmicro.com
    • 127.0.0.1 update.aladdin.com
    • 127.0.0.1 update.authentium.com
    • 127.0.0.1 update.avast.com
    • 127.0.0.1 update.avg.com
    • 127.0.0.1 update.avp.com
    • 127.0.0.1 update.bitdefender.com
    • 127.0.0.1 update.ca.com
    • 127.0.0.1 update.customer.symantec.com
    • 127.0.0.1 update.dispatch.mcafee.com
    • 127.0.0.1 update.download.mcafee.com
    • 127.0.0.1 update.eset.com
    • 127.0.0.1 update.ewido.com
    • 127.0.0.1 update.f-secure.com
    • 127.0.0.1 update.free-av.com
    • 127.0.0.1 update.global.ahnlab.com
    • 127.0.0.1 update.grisoft.com
    • 127.0.0.1 update.hispasec.com
    • 127.0.0.1 update.ikarus-software.at
    • 127.0.0.1 update.kaspersky-labs.com
    • 127.0.0.1 update.kaspersky.com
    • 127.0.0.1 update.liveupdate.symantec.com
    • 127.0.0.1 update.liveupdate.symantecliveupdate.com
    • 127.0.0.1 update.mast.mcafee.com
    • 127.0.0.1 update.mcafee.com
    • 127.0.0.1 update.my-etrust.com
    • 127.0.0.1 update.nai.com
    • 127.0.0.1 update.networkassociates.com
    • 127.0.0.1 update.pandasecurity.com
    • 127.0.0.1 update.quickheal.com
    • 127.0.0.1 update.securityresponse.symantec.com
    • 127.0.0.1 update.sophos.com
    • 127.0.0.1 update.symantec.com
    • 127.0.0.1 update.trendmicro.com
    • 127.0.0.1 update.us.mcafee.com
    • 127.0.0.1 update.virus-buster.com
    • 127.0.0.1 update.viruslist.com
    • 127.0.0.1 update.virustotal.com
    • 127.0.0.1 us.mcafee.com
    • 127.0.0.1 virus-buster.com
    • 127.0.0.1 viruslist.com
    • 127.0.0.1 virustotal.com
    • 127.0.0.1 www.aladdin.com
    • 127.0.0.1 www.authentium.com
    • 127.0.0.1 www.avast.com
    • 127.0.0.1 www.avg.com
    • 127.0.0.1 www.avp.com
    • 127.0.0.1 www.bitdefender.com
    • 127.0.0.1 www.ca.com
    • 127.0.0.1 www.customer.symantec.com
    • 127.0.0.1 www.dispatch.mcafee.com
    • 127.0.0.1 www.download.mcafee.com
    • 127.0.0.1 www.eset.com
    • 127.0.0.1 www.ewido.com
    • 127.0.0.1 www.f-secure.com
    • 127.0.0.1 www.free-av.com
    • 127.0.0.1 www.global.ahnlab.com
    • 127.0.0.1 www.grisoft.com
    • 127.0.0.1 www.hispasec.com
    • 127.0.0.1 www.ikarus-software.at
    • 127.0.0.1 www.kaspersky-labs.com
    • 127.0.0.1 www.kaspersky.com
    • 127.0.0.1 www.liveupdate.symantec.com
    • 127.0.0.1 www.liveupdate.symantecliveupdate.com
    • 127.0.0.1 www.mast.mcafee.com
    • 127.0.0.1 www.mcafee.com
    • 127.0.0.1 www.my-etrust.com
    • 127.0.0.1 www.nai.com
    • 127.0.0.1 www.networkassociates.com
    • 127.0.0.1 www.pandasecurity.com
    • 127.0.0.1 www.quickheal.com
    • 127.0.0.1 www.securityresponse.symantec.com
    • 127.0.0.1 www.sophos.com
    • 127.0.0.1 www.symantec.com
    • 127.0.0.1 www.trendmicro.com
    • 127.0.0.1 www.us.mcafee.com
    • 127.0.0.1 www.virus-buster.com
    • 127.0.0.1 www.viruslist.com
    • 127.0.0.1 www.virustotal.com
  3. Save the file and close the text editor.

Restoring Deleted, Modified, or Overwritten Files

The following file, which was overwritten by the malware (if originally present), can be restored from backup or using installers:

  • %System%\javaw.exe

Deleting Malware-created AUTORUN.INF/s

  1. Right-click Start then click Search... or Find..., depending on the version of Windows you are running.
  2. In the Named input box, type:
    AUTORUN.INF
  3. In the Look In drop-down list, select a drive, then press Enter.
  4. Select the file, then open using Notepad.
  5. Check if the following lines are present in the file:
    [autorun]
    open=RECYCLER\S-1-6-21-2434476531-1645641927-102000330-1542\redmond.exe
    icon=%SystemRoot%\system32\SHELL32.dll
    action=Open Folder to view files
    shell\open=open
    shell\open\command=RECYCLER\S-1-6-21-2434476531-1645641927-102000330-1542\redmond.exe
    shell\open\default=1
  6. If the lines are present, delete the file.
  7. Repeat steps 3 to 6 for AUTORUN.INF files in the remaining removable drives.
  8. Close Search Results.

Important Windows ME/XP Cleaning Instructions

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

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

Running Trend Micro Antivirus

If you are currently running in safe mode, please restart your computer normally before performing the following solution.

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




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