W32.Zatyudi.A

When the worm is executed, it creates the following files:

• C:\WINDOWS\system32\[8-DIGIT HEXADECIMAL NUMBER]\services.exe
• C:\WINDOWS\system32\[8-DIGIT HEXADECIMAL NUMBER]\services.dat
• C:\WINDOWS\winlogon.exe

It then creates the following registry entry, so that it starts when Windows starts:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\"NTservices" = "C:\WINDOWS\system32\[8-DIGIT HEXADECIMAL NUMBER]\services.exe -update"

The worm also modifies the following registry entries, so that it starts when Windows starts:

• HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Winlogon\"Shell" = "Explorer.exe C:\WINDOWS\winlogon.exe" HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SafeBoot\"AlternateShell" = "winlogon.exe -safemode"
• HKEY_USERS\.DEFAULT\Microsoft\Windows NT\CurrentVersion\Winlogon\"Shell" = "Explorer.exe C:\WINDOWS\winlogon.exe"

The worm may then harvest email addresses from files with the following extensions:

• .exe
• .scr
• .com
• .pif
• .cmd
• .wab
• .asp
• .dbx
• .eml
• .htm
• .html
• .jsp
• .msg
• .php
• .shtm
• .shtml
• .txt
• .xml
• .js
• .xml
• .aspx

It will ignore email addresses that contain the following strings:

• @microsoft
• rating@
• anti
• secur
• news
• update
• kasp
• admin
• icrosoft
• support
• ntivi
• unix
• bsd
• nux
• listserv
• certific
• sopho
• avas
• @foo
• @iana
• desk
• free-av
• @messagelab
• winzip
• google
• winrar
• samples
• abuse
• panda
• cafee
• spam
• pgp
• @avp.
• noreply
• local
• root@
• .org
• @sys
• premium
• titanium
• viruz
• virus
• support
• orman
• aladin
• groups
• anyone@
• bugs@
• contract@
• feste
• gold-certs@
• help@
• info@
• nobody@
• noone@
• @sun
• master
• project
• ternal
• fbi
• gmx
• crack
• hack
• code
• ware
• trojan
• clean
• spy
• movsd
• masm
• @pc
• source
• h4ck
• compu
• sales
• catch
• mantec
• defen
• viri
• kill
• cisco
• labs
• trust
• sweep
• winrar
• winzip
• submit
• l0pht
• phreak

The email addresses gathered may be stored in the following file:
C:\Recycled.[8-DIGIT HEXADECIMAL NUMBER]\yudizat.zat

The worm may copy itself to shared folders and removable drives using the following file names:

• Bank mini Games.exe
• Apache_server_831.exe
• Internet Explorer Vista.exe
• Nation Instinct.exe
• Crack Windows vista final release.exe
• Gorilaz complete album lyrics.exe
• Winamp Deluxe pro.exe
• Bank Mini Games complete 2007.exe
• Nero final version 8.exe
• PHP nuke hack 3.exe
• Guitar XP studio.exe
• war games.exe
• Splinter Cell.exe
• e-Gold auto hack v2.1.exe
• New yahoo messenger vista.exe
• Update windows media player 10.exe
• full complete codec pack.exe
• XP Update.exe
• Hawai Beach screen saver.exe
• Britney Screensaver (live).exe
• Defacer tool.exe
• Trojan removal
• eBay userID.exe
• full AVG update 2007 pack.exe
• eBay password.exe
• Yahoo! password.exe
• Soccer Manager 2007.exe
• DeepFreeze Pro full.exe
• Deep_freeze enterprise.exe
• Games Cheats DataBase.exe
• Californian Food v3.exe
• Complete password cracker tool.exe
• GameHouse Collection.exe
  
  Note: These files may also be dropped in random locations.
  

The worm may also randomly create .zip files in various folders on the compromised computer with the any of the following file names:

• Entertainment.zip
• don't touch this!.zip
• my briefcase.zip
• Photo Album Packed.zip
• Deep_freeze_pro8.zip
• Always in memory.rar
• Billing_13_professional.zip
• AVP_N_license.zip
• XP anti hacker.zip

The .zip files contain a copy of the worm with the file name SETUP.exe. It may then copy these .zip files to shared folders and removable drives.

The worm may attempt to connect to the following IP addresses to check network connectivity (using ping.exe) and then send a notification of infection:

• 69.73.169.9
• 216.177.77.9

It may then attempt to download one of the following images:

• [http://]www.imageshack.us/images_[REMOVED]
• [http://]www.ghostspell.com/freak[REMOVED]
• [http://]www.wilkipedia.com/logo[REMOVED]
• [http://]www.geocities.com/paleztinezgr/hack[REMOVED]
• [http://]www.globalframe.com/global_[REMOVED]
• [http://]www.vbstuff.com/yudizat/sour[REMOVED]
• [http://]www.geocities.com/huseindam1/hack[REMOVED]
• [http://]www.geocities.com/rinkdal3/hack[REMOVED]
• [http://]www.zone-h.com/defacer/view[REMOVED]
• [http://]yz_black.cjb.net/yz_black/blac[REMOVED]
• [http://]yz_red.cjb.net/yz_red/red[REMOVED]
• [http://]yz_green.cjb.net/yz_green/gree[REMOVED]
• [http://]yz_yellow.cjb.net/yz_yellow/yello[REMOVED]
• [http://]yz_white.cjb.net/yz_white/whit[REMOVED]
• [http://]yz_gray.cjb.net/yz_gray/gray[REMOVED]
• [http://]yz_violet.cjb.net/yz_violet/viole[REMOVED]
• [http://]yz_silver.cjb.net/yz_silver/silve[REMOVED]
• [http://]yz_hot.cjb.net/yz_hot/hot[REMOVED]
• [http://]yz_cool.cjb.net/yz_cool/cool[REMOVED]
• [http://]yz_freeze.cjb.net/yz_freeze/freez[REMOVED]
• [http://]yz_slow.cjb.net/yz_slow/slow[REMOVED]
• [http://]yz_fast.cjb.net/yz_fast/fast[REMOVED]
• [http://]yz_strong.cjb.net/yz_strong/stron[REMOVED]
• [http://]yz_happy.cjb.net/yz_happy/happ[REMOVED]
• [http://]yz_sad.cjb.net/yz_sad/sad[REMOVED]
• [http://]yz_cry.cjb.net/yz_cry/cry[REMOVED]

The worm then attempts to end all processes and services whose name, associated window, or description contain the following strings:

• SysMech
• PDFIND
• avtask
• mav
• process
• ccapp
• avgemc
• snaps
• rstrui
• syslove
• sstray
• thread
• mcvsescn
• poproxy
• xpshare
• systray
• ashmaisv
• aswupdsv
• nvc
• cclaw
• njeeves
• nipsvc
• update
• vptray
• opscan
• nopdb
• ccapp
• ctfmon
• zlh
• avgupsvc
• removal
• virus
• AGENTSVR
• ANTI
• MONITOR
• APLICA32
• APVXDWIN
• ATCON
• GUARD
• ATRO55EN
• WATCH
• AUTODOWN
• AUTOTRACE
• AUTOUPDATE
• AVCONSOL
• AVGSERV9
• AVLTMAIN
• AVPUPD
• AVSYNMGR
• AVWUPD32
• AVXQUAR
• AVprotect9x
• BD_PROFESSIONAL
• BIDEF
• BIDSERVER
• BIPCP
• BIPCPEVALSETUP
• BISP
• BLACKD
• BLACKICE
• BOOTWARN
• BORG2
• BS120
• CDP
• CFGWIZ
• CFIADMIN
• CFIAUDIT
• CFINET
• CFINET32
• CLEAN
• CLEAN32
• CLEANER
• CLEANER3
• CLEANPC
• CMGRDIAN
• CMON016
• CPD
• CPF9X206
• CWNB181
• CWNTDWMO
• config
• killbox
• hijackthis
• DEFWATCH
• DEPUTY
• DPF
• DPFSETUP
• DRWATSON
• DRWEBUPW
• ENT
• ESCANH95
• ESCANHNT
• ESCANV95
• EXANTIVIRUS-CNET
• FAST
• FIREWALL
• FLOWPROTECTOR
• FP-WIN_TRIAL
• FRW
• FSAV
• FSAV530STBYB
• GBMENU
• GBPOLL
• GUARD
• GUARDDOG
• HACKTRACERSETUP
• HTLOG
• HWPE
• IAMAPP
• IAMSERV
• ICLOAD95
• ICLOADNT
• ICMON
• ICMON32
• sysmech6
• sysmech5
• ICSSUPPNT
• ICSUPP95
• ICSUPPNT
• IFW2000
• IPARMOR
• IRIS
• JAMMER
• KAVLITE40ENG
• KAVPERS40ENG
• KERIO-PF-213-EN-WIN
• KERIO-WRL-421-EN-WIN
• KERIO-WRP-421-EN-WIN
• KILLPROCESSSETUP161
• LDPRO
• LOCALNET
• LOCKDOWN
• LOCKDOWN2000
• LSETUP
• LUALL
• LUCOMSERVER
• LUINIT
• MCAGENT
• MCUPDATE
• MFW2EN
• MFWENG3.02D30
• MGUI
• MINILOG
• MOOLIVE
• MRFLUX
• CONFIG32
• MSINFO32
• MSSMMC32
• MU0311AD
• NAV80TRY
• NAVAPW32
• NAVDX
• NAVSTUB
• NAVW32
• NC2000
• NCINST4
• admin
• NDD32
• NEOMONITOR
• NETARMOR
• NETINFO
• NETMON
• NETSCANPRO
• HUNTER
• NISSERV
• NMAIN
• NORTON
• NPF
• NPROTECT
• NSCHED32
• NTVDM
• NUPGRADE
• NVARCH16
• NWINST4
• NWTOOL16
• NavShExt.dll
• OSTRONET
• OUTPOST
• OUTPOST
• PADMIN
• PANIXK
• PAVPROXY
• PCC2002S902
• PCC2K_76_1436
• PCCIOMON
• PCDSETUP
• PCFWALLICON
• PCIP10117_0
• PDSETUP
• PERISCOPE
• PERSFW
• PF2
• PFWADMIN
• PINGSCAN
• PLATIN
• PROTECTX
• PSPF
• QCONSOLE
• QSERVER
• RESCUE
• watch
• watcher
• RRGUARD
• RSHELL
• RULAUNCH
• SAFEWEB
• SAVSCAN
• SBSERV
• SETUPVAMEEVAL
• SETUP_FLOWPROTECTOR_US
• SFC
• SGSSFW32
• SHELLSPYINSTALL
• SYSEDIT
• SymWSC
• TAUMON
• TAUSCAN
• TRACERT
• TRJSCAN
• TRJSETUP
• TROJANTRAP
• UNDOBOOT
• VBCMSERV
• VBCONS
• VBUST
• VIRUSMDPERSONALFIREWALL
• W32DSM
• WEBSCANX
• WHOSWATCHINGME
• WINRECON
• WNT
• WRADMIN
• WRCTRL
• WSBGATE
• WYVERNWORKSFIREWALL
• XPF202EN
• ZONEALARM
• ccApp
• ccEvtMgr
• navapsvc
• norman
• workstation
• autoupdate
• avast
• internals
• ContactKeeper129
• antivir
• avg
• aawsepersonal
• avgwb.dat
• ultraedit
• hiew
• memhack
• systemhack
• finder
• engine
• cracker
• cheat
• anti
• hacker
• killer
• machine
• fix
• fixer
• ner
• er44
• er40
• er10
• er5
• spy
• Dump
• fusion
• virus
• system
• f10
• er10
• jack
• rip
• guard
• diskmon
• regmon
• monitor
• debug
• MEMGUTT
• nmap
• rminstall
• ator
• secure
• security
• center
• control
• panda
• sophos
• prot
• protex
• protect
• regmonnt
• ware
• view
• viewer
• washer
• admin
• administrator
• secret
• show
• stealth
• hide
• awake
• visible
• dump
• api
• crc
• procexp
• hex
• workshop
• ver
• licode
• codeli
• hacking
• mfwenu3.02r
• vsc601ai
• vs0602AU
• upswplug
• rescue
• RShelln
• shield
• stealth
• scrubber
• LUSETUP
• scan
• NavDX
• NU2002
• Pavjobs
• PAVSRV50
• Pavw
• Repairnt
• zapSetup3026
• anty
• Pavsched
• Pavclshe
• pavcl.msg
• pavcl
• Inicio
• Iface
• Avengine
• Apvxdwin
• upgrader
• TRJSETUP
• wgsetup
• WINPROXY
• maker
• crack
• hack
• procviewer
• lyze
• yzer
• yzing
• pest
• patrol
• viruz
• virii
• viren
• stop
• attack
• defend
• stoper
• stoped
• exploit
• monitoring
• scan
• sav
• rav
• lav
• known
• pav
• kav
• yav
• tav
• nav
• hidden
• hidding
• die
• admin
• netcat
• nmap
• softice
• softice32
• tools
• xav
• abuse
• abuser
• tactic
• weapon
• rock
• strike
• special
• ddos
• flicker
• sniff
• access
• proc
• proce
• memory
• frog
• trap
• catch
• frogging
• grabber
• graber
• grabbing
• kick
• kicker
• stole
• aware
• freeze
• freezing
• struct
• death
• Avast
• ashBug
• ashDisp
• ashChest
• ashLogV
• ashMaiSv
• ashPopWz
• ashQuick
• ashSimpl
• ashSkPcc
• ashSkPck
• aswBoot
• aswUpdSv
• sched
• ccsetmgr
• pavprsrv
• navsetup
• lrsetup
• lucoms~1
• nprotect
• cfgwiz
• symlcsvc
• luall
• navapsvc
• navw32
• wisptis
• inocit
• stopper
• realmon
• monxp
• avconsol
• alogserv
• webscanx
• mcshield
• vshwin32
• vsstat
• avsynmgr
• netstat
• ipconfig
• nmap
• wmiprvse
• toolz
• hacker
• cracker
• snipper
• avengine
• pavprsrv
• pavsrv51
• apvxdwin
• LordPE

Recommendations

Symantec Security Response encourages all users and administrators to adhere to the following basic security "best practices":

• Use a firewall to block all incoming connections from the Internet to services that should not be publicly available. By default, you should deny all incoming connections and only allow services you explicitly want to offer to the outside world.
• Enforce a password policy. Complex passwords make it difficult to crack password files on compromised computers. This helps to prevent or limit damage when a computer is compromised.
• Ensure that programs and users of the computer use the lowest level of privileges necessary to complete a task. When prompted for a root or UAC password, ensure that the program asking for administration-level access is a legitimate application.
• Disable AutoPlay to prevent the automatic launching of executable files on network and removable drives, and disconnect the drives when not required. If write access is not required, enable read-only mode if the option is available.
• Turn off file sharing if not needed. If file sharing is required, use ACLs and password protection to limit access. Disable anonymous access to shared folders. Grant access only to user accounts with strong passwords to folders that must be shared.
• Turn off and remove unnecessary services. By default, many operating systems install auxiliary services that are not critical. These services are avenues of attack. If they are removed, threats have less avenues of attack.
• If a threat exploits one or more network services, disable, or block access to, those services until a patch is applied.
• Always keep your patch levels up-to-date, especially on computers that host public services and are accessible through the firewall, such as HTTP, FTP, mail, and DNS services.
• Configure your email server to block or remove email that contains file attachments that are commonly used to spread threats, such as .vbs, .bat, .exe, .pif and .scr files.
• Isolate compromised computers quickly to prevent threats from spreading further. Perform a forensic analysis and restore the computers using trusted media.
• Train employees not to open attachments unless they are expecting them. Also, do not execute software that is downloaded from the Internet unless it has been scanned for viruses. Simply visiting a compromised Web site can cause infection if certain browser vulnerabilities are not patched.
• If Bluetooth is not required for mobile devices, it should be turned off. If you require its use, ensure that the device's visibility is set to "Hidden" so that it cannot be scanned by other Bluetooth devices. If device pairing must be used, ensure that all devices are set to "Unauthorized", requiring authorization for each connection request. Do not accept applications that are unsigned or sent from unknown sources.
• For further information on the terms used in this document, please refer to the Security Response glossary.

Summary