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MyDoom.U

Classification

Category: Malware

Type: Email-Worm

Aliases: MyDoom.U

Summary


A new variant of MyDoom worm - Mydoom.U, was found on September 9th, 2004. This worm variant is similar to previous ones. It spreads in emails with different subject and body texts, downloads and activates a backdoor.

Removal


Automatic action

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Eliminating a Local Network Outbreak

If the infection is in a local network, please follow the instructions on this webpage:

Knowledge Base

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About the product

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Submit a sample

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Technical Details


The worm is a PE ( Portable Executable) file 18200 bytes long packed with UPX file compressor. The unpacked file's size is over 44 kilobytes.

Installation to system

When run, the worm creates a mutex 'qwedefacedRDE', copies itself as WINSPF32.EXE to Windows System Directory and creates a startup key for that file in System Registry:

  • [HKCU\Software\Microsoft\Windows\CurrentVersion\Run] "WinSPF" = "%WinSysDir%\winspf32.exe"

where %WinSysDir% represents Windows System directory.

Additionally, the worm copies itself to the 'Start Menu\Programs\Startup\' folder of a current user as RX32HH00.EXE file.

Spreading in emails

The worm spreads by sending its infected attachment to all email addresses found on an infected computer. The worm looks for email addresses in Windows Address Book and in the files with the following extensions:

  • wab
  • xls
  • vbs
  • uin
  • txt
  • tbb
  • stm
  • sht
  • php
  • msg
  • mht
  • jsp
  • htm
  • eml
  • dht
  • dbx
  • cgi
  • cfg
  • asp

The worm avoids sending emails to email addresses that contain any of the following substrings:

  • avp.
  • syman
  • icrosof
  • panda
  • sopho
  • borlan
  • inpris
  • example
  • mydomai
  • nodomai
  • ruslis
  • icrosoft
  • .gov
  • gov.
  • .mil
  • @foo.
  • @iana
  • spam
  • unix
  • linux
  • kasp
  • antivi
  • messagelabs
  • support
  • berkeley
  • unix
  • math
  • mit.e
  • gnu
  • fsf.
  • ibm.com
  • google
  • kernel
  • linux
  • fido
  • usenet
  • iana
  • ietf
  • rfc-ed
  • sendmail
  • arin.
  • ripe.
  • isi.e
  • isc.o
  • secur
  • acketst
  • pgp
  • tanford.e
  • utgers.ed
  • mozilla
  • icq.com
  • admin
  • icrosoft
  • support
  • ntivi
  • unix
  • bsd
  • linux
  • listserv
  • certific
  • google
  • accoun
  • abuse
  • upport
  • www
  • root
  • info
  • samples
  • postmaster
  • rating
  • root
  • news
  • webmaster
  • noone
  • noreply
  • nobody
  • nothing
  • anyone
  • someone
  • rating
  • site
  • contact
  • support
  • somebody
  • privacy
  • service
  • help
  • submit
  • feste
  • gold-certs

The subject of infected emails is selected from the following variants:

  • hello
  • here
  • hi
  • Hi!
  • important
  • Information
  • my
  • News
  • Notice again
  • Private document
  • Re: Hello
  • Re: Hi
  • Re: Message
  • Re: Proof of concept
  • Re: Question
  • Re: Status
  • Re: Your document
  • read it immediately
  • Thank you!
  • thanks!
  • You win!

The body of infected emails is selected from the following variants:

  • Can you confirm it?
  • For further details see the attachment....
  • For more details see the attachment.
  • Monthly news report.
  • Please answer quickly!
  • Please confirm!
  • Please read the attached file!
  • Please read the document.
  • Please see the attached file for detail...
  • Thanks!
  • Waiting for a Response. Please read the...
  • Your archive is attached.
  • Your requested mail has been attached.
  • I have attached document.
  • Please confirm the document.
  • Please read the attached file.
  • Please read the important document.
  • See attached file for details.
  • See the file.
  • lol!
  • fun!
  • fun game!
  • game
  • apply patch.
  • apply this patch!
  • You are infected by virus. Run this exe...
  • Virus removal tool
  • Thanks!
  • relax
  • See the file.
  • New game
  • fun photos
  • screensaverlol!

The worm can send itself as an executable attachment or in a ZIP archive with one of the following names:

  • document.doc .pif
  • doc.doc .pif
  • mesg.doc .pif
  • report.doc .pif
  • review.doc .pif
  • bill.doc .pif
  • doc.rtf .pif
  • mesg.rtf .pif
  • report.rtf .pif
  • review.rtf .pif
  • bill.rtf .pif
  • doc.txt .pif
  • mesg.txt .pif
  • report.txt .pif
  • review.txt .pif
  • bill.txt .pif
  • rep.txt .pif
  • Message.html .pif
  • document.zip
  • doc.zip
  • report.zip
  • new.zip
  • doc.zip
  • bill.zip
  • data.zip
  • details.zip
  • file.zip
  • info.zip
  • information.zip
  • letter.zip
  • message,.zip
  • file.exe
  • game.exe
  • photo.exe
  • pic.exe
  • new.exe
  • patch.exe
  • antivirus.exe
  • fun.scr
  • lol.scr

The worm can also attach a fake virus scan report to its message:

where the antivirus mentioned can be any of the following:

  • Norton AntiVirus - www.symantec.de
  • F-Secure AntiVirus - www.f-secure.com
  • Norman AntiVirus - www.norman.com
  • Panda AntiVirus - www.pandasoftware.com
  • Kaspersky AntiVirus - www.kaspersky.com
  • MC-Afee AntiVirus - www.mcafee.com
  • Bitdefender AntiVirus - www.bitdefender.com
  • MessageLabs AntiVirus - www.messagelabs.com

The worm fakes the sender's address and uses the following list of first names to compose the fake address:

  • James
  • John
  • Robert
  • Michael
  • William
  • David
  • Richard
  • Charles
  • Joseph
  • Thomas
  • Christopher
  • Daniel
  • Paul
  • Mark
  • Donald
  • George
  • Kenneth
  • Steven
  • Edward
  • Brian
  • Ronald
  • Anthony
  • Kevin
  • Jason
  • Matthew
  • Gary
  • Timothy
  • Jose
  • Larry
  • Jeffrey
  • Frank
  • Scott
  • Eric
  • Stephen
  • Andrew
  • Raymond
  • Gregory
  • Joshua
  • Jerry
  • Dennis
  • Walter
  • Patrick
  • Peter
  • Harold
  • Douglas
  • Henry
  • Carl
  • Ricky
  • Troy
  • Randall
  • Barry
  • Alexander
  • Bernard
  • Mario
  • Leroy
  • Francisco
  • Marcus
  • Micheal
  • Theodore
  • Clifford
  • Miguel
  • Oscar
  • Jay
  • Jim
  • Tom
  • Calvin
  • Alex
  • Jon
  • Ronnie
  • Bill
  • Lloyd
  • Tommy
  • Leon

It uses the following list of last names to compose the fake address:

  • Smith
  • Johnson
  • Williams
  • Jones
  • Brown
  • Davis
  • Miller
  • Wilson
  • Moore
  • Taylor
  • Anderson
  • Thomas
  • Jackson
  • White
  • Harris
  • Martin
  • Thompson
  • Garcia
  • Martinez
  • Robinson
  • Clark
  • Rodriguez
  • Lewis
  • Lee
  • Walker
  • Hall
  • Allen
  • Young
  • Hernandez
  • King
  • Wright
  • Lopez
  • Hill
  • Scott
  • Green
  • Adams
  • Baker
  • Gonzalez
  • Nelson
  • Carter
  • Mitchell
  • Perez
  • Roberts
  • Turner
  • Phillips
  • Campbell
  • Parker
  • Cruz
  • Marshall
  • Ortiz
  • Gomez
  • Murray
  • Freeman
  • Wells
  • Webb
  • Simpson
  • Stevens
  • Tucker
  • Porter

It uses the following list of domain names to compose the fake address:

  • @dailymail.co.uk
  • @mail.com
  • @aol.com
  • @hotmail.com
  • @gmx.net
  • @t-online.de
  • @yahoo.co.uk
  • @msn.com
  • yahoo.com
  • cox.net
Downloading a backdoor

The worm downloads a backdoor from one of the websites and activates it. The backdoor is known as 'Surila.I' or 'BackDoor-CEB.c' and is downloaded from the following websites:

  • www.planetboredom.net
  • vugs.geog.uu.nl
  • www.ach.ch
  • www.hiw.kuleuven.ac.be
  • www.surrenderzeeland.nl
  • www.llc.unibo.it
Limited lifecycle

After September 20th, 2004, 01:18:31 the worm stops working and deletes its file from the hard drive.