Discovered: April 27, 2004
Updated: February 13, 2007 12:22:15 PM
Also Known As: Backdoor.Agobot.gen [Kaspersky, WORM_AGOBOT.JF [Trend], WORM_AGOBOT.JO [Trend]
Type: Worm
Systems Affected: Windows



W32.Gaobot.AFJ is a worm that spreads through open network shares, backdoors that the Beagle and Mydoom worms install, and several Windows vulnerabilities, including:

The worm can also act as a backdoor server program and attack other systems. Additionally, the worm attempts to stop the process of many antivirus and security programs.




A variant discovered on May 12, 2004 attempts to spread using W32.Sasser.Worm. It does this by injecting code into the "avserve.exe" process, so that when the Sasser worm attempts to propagate, it sends Gaobot to the remote system instead of Sasser. This variant creates a file named "wormride.dll" in the System directory.

Antivirus Protection Dates

  • Initial Rapid Release version April 28, 2004
  • Latest Rapid Release version June 10, 2018 revision 023
  • Initial Daily Certified version April 28, 2004
  • Latest Daily Certified version June 11, 2018 revision 001
  • Initial Weekly Certified release date April 28, 2004

Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

Writeup By: Kaoru Hayashi

Discovered: April 27, 2004
Updated: February 13, 2007 12:22:15 PM
Also Known As: Backdoor.Agobot.gen [Kaspersky, WORM_AGOBOT.JF [Trend], WORM_AGOBOT.JO [Trend]
Type: Worm
Systems Affected: Windows



When W32.Gaobot.AFJ is executed, it performs the following actions:

  1. Copies itself as one of the following:
    • %System%\msiwin84.exe
    • %System%\Microsoft.exe
    • %System%\WinMsrv32.exe
    • %System%\soundcontrl.exe
    • %System%\msawindows.exe

  2. Adds one of these values:

    "Microsoft Update"="msiwin84.exe"
    "Microsoft Update"="Microsoft.exe"
    "WinMsrv32"="WinMsrv32.exe"
    "soundcontrl"="soundcontrl.exe"
    "Microsoft Update"="msawindows.exe"

    to the registry keys:

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
    RunServices

    so that W32.Gaobot.AFJ runs when you start Windows.

  3. Adds the following lines to the %System%\drivers\etc\hosts file, so that any attempts to connect to these Web sites fail:

    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 www.trendmicro.com
    127.0.0.1 www.grisoft.com

  4. Terminates the processes of a large number of antivirus and security applications. Refer to the "Processes" section for a complete list of process names.

  5. Terminates the following processes:

    irun4.exe
    Ssate.exe
    i11r54n4.exe
    winsys.exessgrate.exe
    d3dupdate.exe
    bbeagle.exerate.exe

  6. Sends HTTP POST messages containing large amounts of data (250 KB per POST message) to the following hosts:

    www.ryan1918.net
    www.ryan1918.org
    www.ryan1918.com
    yahoo.co.jp
    www.nifty.com
    www.d1asia.com
    www.st.lib.keio.ac.jp
    www.lib.nthu.edu.tw
    www.above.net
    www.level3.com
    nitro.ucsc.edu
    www.burst.net
    www.cogentco.com
    www.rit.edu
    www.nocster.com
    www.verio.com
    www.stanford.edu
    www.xo.net
    de.yahoo.com
    www.belwue.de
    www.switch.ch
    www.1und1.deverio.fr
    www.utwente.nl
    www.schlund.net

  7. Opens a randomly selected TCP port and sends a copy of itself to any process connecting to that port.

  8. Connects to a remote IRC server and awaits commands from the remote attacker. The backdoor allows the attacker to perform the following actions on a compromised system:

    Run commands
    Retrieve files via FTP and HTTP
    Retrieve data from the registry
    Restart the computer
    List processes
    Kill a particular process
    Terminate Windows services
    Perform HTTP, ICMP, SYN, and UDP floods
    Retrieve email addresses stored on the computer
    Retrieve a list of email addresses via HTTP
    Retrieve a given URL
    Sniff HTTP, FTP, and IRC traffic
    Steal the Windows product ID and the CD keys of various video games

  9. Attempts to propagate to other systems using the following methods:

    Sending itself to the backdoor port that the Beagle family of worms opens.
    Sending itself to the backdoor port that the Mydoom family of worms opens.
    Exploits the Microsoft Windows DCOM RPC Interface Buffer Overrun Vulnerability.
    Exploits the Microsoft Windows Workstation Service Remote Buffer Overflow Vulnerability.
    Exploits the Microsoft Windows Local Security Authority Service Remote Buffer Overflow.

  10. Attempts to copy itself to other computers through the following remote administrative SMB shares:
    c$
    d$
    e$
    print$
    admin$
    ipc$

    using the following user names and passwords, as well as any user names found using NetUserEnum():

    User name:

    aaa
    abc
    Admin
    admin
    administrador
    Administrador
    Administrat
    Administrateur
    administrator
    admins
    anonymous
    asdf
    backup
    ball
    Benutzer
    bill
    black
    box
    calcolatore
    colin
    computadora
    computer
    Convidado
    Coordinatore
    data
    database
    Default
    Dell
    dickerik
    fuck
    Gast
    george
    Guest
    home
    Invit
    Inviter
    jim
    kanri
    kanri-shakarl
    kate
    lab
    mark
    mary
    master
    mgmt
    mike
    mypc
    mysql
    null
    OEM
    office
    oracle
    Ospite
    OWNER
    owner
    Owner
    patrick
    peter
    poop
    private
    qwer
    rat
    rio
    root
    sasecret
    server
    sexsped
    spedsql
    sqlagent
    sql-server
    staceystacy
    Standard
    stefan
    steve
    steven
    student
    sybase
    system
    teacher
    temp
    Test
    tim
    tomuser
    User
    Usu
    Utente
    Utilisateur
    Verwalter
    web
    webmaster
    win
    workplace
    wwwadmin
    xyz

    Password:

    !@#$
    !@#$%
    !@#$%^
    !@#$%^&
    !@#$%^&*
    000000
    00000000
    007
    110
    111
    111111
    11111111
    121212
    123
    123123
    1234
    12345
    123456
    1234567
    12345678
    123456789
    1234qwer
    123abc
    123asd
    123qwe
    2002
    2004
    2600
    54321
    654321
    666
    88888888
    abc123
    abcd
    ACCESS
    admin123
    ADMINISTRATOR
    alpha
    asdfgh
    asdfghjkl
    ASPbaby
    backdoor
    BACKUP
    Box
    BOX
    box
    changeme
    CNN
    crash
    devil
    dude
    enablef
    eds
    fish
    foobar
    f**ked
    gaygod
    godblessyou
    hax
    homework
    idiot
    ihavenopass
    Internet
    kidsleet
    linux
    LOCAL
    Login
    lol
    lovemetal
    mybaby
    mybox
    mypass
    mypc
    noob
    oracle
    own
    owned
    pass
    PASSWD
    passwd
    password
    Password
    password123
    patpatrick
    penis
    PHP
    poiuytrewq
    porn
    private
    pussy
    pwdpwned
    qwerty
    qwertyuiop
    r00t
    red123
    ROOT
    rooted
    school
    secret
    secrets
    SERVER
    sex
    share
    super
    superman
    supersecret
    sybase
    SYSTEM
    TEMP
    TEST
    test123
    UNIX
    vagina
    werty
    wh0re
    whore
    windows2k
    windows98
    windowsME
    WindowsXP
    windoze
    work
    xxx
    xxyyzz
    yxcv
    zxcv
    zxcvbnm

  11. Copies itself and executes on any remote shares to which it successfully authenticates.

  12. Schedules a Network job to run the worm on the remote system.

Processes
W32.Gaobot.ADV attempts to terminate the following processes, mentioned in step 4:

_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
AVWIN95.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
Claw95.EXE
CLAW95CF.EXE
CLEAN.EXE
CLEANER.EXE
CLEANER3.EXE
CLEANPC.EXE
CLICK.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
ESCANH95.EXE
ESCANHNT.EXE
ESCANV95.EXE
ESPWATCH.EXE
ETHEREAL.EXE
ETRUSTCIPE.EXE
EVPN.EXE
EXANTIVIRUS-CNET.EXE
EXE.AVXW.EXE
EXPERT.EXE
EXPLORE.EXE
F-AGNT95.EXE
F-PROT.EXE
F-PROT95.EXE
F-STOPW.EXE
FAMEH32.EXE
FAST.EXE
FCH32.EXE
FIH32.EXE
FINDVIRU.EXE
FIREWALL.EXE
FLOWPROTECTOR.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
ICLOAD95.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
IPARMOR.EXE
IRIS.EXE
ISASS.EXE
ISRV95.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
NAVENGNAVEX15.NAVLU32.EXE
NAVLU32.EXE
NAVNT.EXE
NAVSTUB.EXE
NAVW32.EXE
NAVWNT.EXE
NC2000.EXE
NCINST4.EXE
NDD32.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
PCC2002S902.EXE
PCC2K_76_1436.EXE
PCCIOMON.EXE
PCCNTMON.EXE
PCCWIN97.EXE
PCCWIN98.EXE
PCDSETUP.EXE
PCFWALLICON.EXE
PCIP10117_0.EXE
PCSCAN.EXE
PDSETUP.EXE
PENIS.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
PUSSY.EXE
PVIEW95.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
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
SCRSVR.EXE
SCVHOST.EXE
SD.EXE
SERV95.EXE
SERVICE.EXE
SERVLCE.EXE
SERVLCES.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
TASKMO.EXE
TASKMON.EXE
TAUMON.EXE
TBSCAN.EXE
TC.EXE
TCA.EXE
TCM.EXE
TDS-3.EXE
TDS2-98.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
WGFE95.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


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.

Writeup By: Kaoru Hayashi

Discovered: April 27, 2004
Updated: February 13, 2007 12:22:15 PM
Also Known As: Backdoor.Agobot.gen [Kaspersky, WORM_AGOBOT.JF [Trend], WORM_AGOBOT.JO [Trend]
Type: Worm
Systems Affected: Windows


Removal using the Removal Tool
Symantec Security Response has developed a removal tool to clean the infections of W32.Gaobot.AFJ. This is the preferred method in most cases.

Manual Removal
The following instructions pertain to all current and recent Symantec antivirus products, including the Symantec AntiVirus and Norton AntiVirus product lines.

  1. Disable System Restore (Windows Me/XP).
  2. Delete the lines that were added to the Windows Hosts file.
  3. Update the virus definitions.
  4. Restart the computer in Safe mode or VGA mode.
  5. Run a full system scan and delete all the files detected as W32.Gaobot.AFJ.
  6. Reverse the changes made to the registry.
For details on each of these steps, read the following instructions.

1. To disable System Restore (Windows Me/XP)
If you are running Windows Me or Windows XP, we recommend that you temporarily turn off System Restore. Windows Me/XP uses this feature, which is enabled by default, to restore the files on your computer in case they become damaged. If a virus, worm, or Trojan infects a computer, System Restore may back up the virus, worm, or Trojan on the computer.

Windows prevents outside programs, including antivirus programs, from modifying System Restore. Therefore, antivirus programs or tools cannot remove threats in the System Restore folder. As a result, System Restore has the potential of restoring an infected file on your computer, even after you have cleaned the infected files from all the other locations.

Also, a virus scan may detect a threat in the System Restore folder even though you have removed the threat.

For instructions on how to turn off System Restore, read your Windows documentation, or one of the following articles:
Note: When you are completely finished with the removal procedure and are satisfied that the threat has been removed, re-enable System Restore by following the instructions in the aforementioned documents.

For additional information, and an alternative to disabling Windows Me System Restore, see the Microsoft Knowledge Base article, "Antivirus Tools Cannot Clean Infected Files in the _Restore Folder," Article ID: Q263455.


2. To delete the added lines from the Windows Hosts file


Note: The location of the Hosts file may vary and some computers may not have this file. For example, if the file exists in Windows 98, it will usually be in C:\Windows; and it is located in the C:\WINNT\system32\drivers\etc folder in Windows 2000. There may also be multiple copies of this file in different locations.

Follow the instructions for your operating system:
  • Windows 95/98/Me/NT/2000
    1. Click Start, point to Find or Search, and then click Files or Folders.
    2. Make sure that "Look in" is set to (C:) and that "Include subfolders" is checked.
    3. In the "Named" or "Search for..." box, type:

      hosts

    4. Click Find Now or Search Now.
    5. For each Hosts file that you find, right-click the file, and then click "Open With."
    6. Deselect the "Always use this program to open this program" check box.
    7. Scroll through the list of programs and double-click Notepad.
    8. When the file opens, delete all the entries in the Hosts file, except for the following line:

      127.0.0.1     localhost

    9. Close Notepad and save your changes when prompted.

  • Windows XP
    1. Click Start, and then click Search.
    2. Click All files and folders.
    3. In the "All or part of the file name" box, type:

      hosts

    4. Verify that "Look in" is set to "Local Hard Drives" or to (C:).
    5. Click "More advanced options."
    6. Check "Search system folders."
    7. Check "Search subfolders."
    8. Click Search.
    9. Click Find Now or Search Now.
    10. For each Hosts file that you find, right-click the file, and then click "Open With."
    11. Deselect the "Always use this program to open this program" check box.
    12. Scroll through the list of programs and double-click Notepad.
    13. When the file opens, delete all the entries in the Hosts file except for the following line:

      127.0.0.1     localhost

3. To update the virus definitions
Symantec Security Response fully tests all the virus definitions for quality assurance before they are posted to our servers. There are two ways to obtain the most recent virus definitions:
  • Running LiveUpdate, which is the easiest way to obtain virus definitions: These virus definitions are posted to the LiveUpdate servers once each week (usually on Wednesdays), unless there is a major virus outbreak. To determine whether definitions for this threat are available by LiveUpdate, refer to the Virus Definitions (LiveUpdate).
  • Downloading the definitions using the Intelligent Updater: The Intelligent Updater virus definitions are posted on U.S. business days (Monday through Friday). You should download the definitions from the Symantec Security Response Web site and manually install them. To determine whether definitions for this threat are available by the Intelligent Updater, refer to the Virus Definitions (Intelligent Updater).

    The Intelligent Updater virus definitions are available: Read "How to update virus definition files using the Intelligent Updater" for detailed instructions.

4. To restart the computer in Safe mode or VGA mode

Shut down the computer and turn off the power. Wait for at least 30 seconds, and then restart the computer in Safe mode or VGA mode.
  • For Windows 95, 98, Me, 2000, or XP users, restart the computer in Safe mode. For instructions, read the document, "How to start the computer in Safe Mode."
  • For Windows NT 4 users, restart the computer in VGA mode.

5. To scan for and delete the infected files
  1. Start your Symantec antivirus program and make sure that it is configured to scan all the files.
  2. Run a full system scan.
  3. If any files are detected as infected with W32.Gaobot.AFJ, click Delete.


6. To reverse the changes made to the registry


WARNING: Symantec strongly recommends that you back up the registry before making any changes to it. Incorrect changes to the registry can result in permanent data loss or corrupted files. Modify the specified keys only. Read the document, "How to make a backup of the Windows registry ," for instructions.
  1. Click Start, and then click Run. (The Run dialog box appears.)
  2. Type regedit

    Then click OK. (The Registry Editor opens.)

  3. Navigate to the key:

    HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run

  4. In the right pane, delete any of these values:

    "Microsoft Update"="msiwin84.exe"
    "Microsoft Update"="Microsoft.exe"
    "WinMsrv32"="WinMsrv32.exe"
    "soundcontrl"="soundcontrl.exe"
    "Microsoft Update"="msawindows.exe"

  5. Do one of the following:
    • On Windows NT/2000/XP: Exit the Registry Editor, and then restart the computer in Normal mode.
    • On Windows 95/98/Me computers: Proceed with step f.

  6. Navigate to the key:

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
    RunServices

  7. In the right pane, delete the value:

    "Microsoft Update"="msiwin84.exe"

    or:

    "Microsoft Update"="Microsoft.exe"

    or:

    "WinMsrv32"="WinMsrv32.exe"

    or:


    "soundcontrl"="soundcontrl.exe"

  8. Exit the Registry Editor and restart the computer in Normal mode.



Writeup By: Kaoru Hayashi