Discovered: April 24, 2004
Updated: February 13, 2007 12:21:57 PM
Type: Worm
Systems Affected: Windows


The W32.Gaobot.ADX worm:

  • Is a worm that spreads through open network shares, several Windows vulnerabilities, and backdoors that the Beagle and Mydoom families of worms install
  • Can act as a backdoor server program and attack other systems
  • Attempts to kill the process of many antivirus and security applications


Antivirus Protection Dates

  • Initial Rapid Release version April 24, 2004
  • Latest Rapid Release version September 28, 2010 revision 054
  • Initial Daily Certified version April 24, 2004
  • Latest Daily Certified version September 28, 2010 revision 036
  • Initial Weekly Certified release date April 26, 2004

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

Writeup By: Fergal Ladley

Discovered: April 24, 2004
Updated: February 13, 2007 12:21:57 PM
Type: Worm
Systems Affected: Windows


W32.Gaobot.ADX is a worm that spreads through open network shares and several Windows vulnerabilities. The worm also propagates through backdoors that the Beagle and Mydoom families of worms install.

When W32.Gaobot.ADX runs, it does the following:

  1. Copies itself as %System%\Msconf.exe.


    Note: %System% is a variable. The worm locates the System folder and copies itself to that location. By default, this is C:\Windows\System (Windows 95/98/Me), C:\Winnt\System32 (Windows NT/2000), or C:\Windows\System32 (Windows XP).

  2. Adds the value:

    "Video Process="Msconf.exe"

    to the registry keys:

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\RunServices

  3. Creates the registry key:

    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Video Process

    and populates it with the following values:

    Display Name=Video Process
    ErrorControl=0x00000001
    FailureActions=ff ff ff ff 00 00 00 00 00 00 00 00 01 00 00 00 58 A9 0D
    00 01 00 00 00 01 00 00 00
    ImagePath="%System%\msconf.exe" -service
    ObjectName=LocalSystem
    Start=0x00000002
    Type=0x00000020
    Enum\0=Root\LEGACY_VIDEO_PROCESS\0000
    Enum\Count=0x00000001
    Enum\NextInstance=0x00000001
    Security\Security=<hex string>

  4. Attempts to terminate the following processes, most of which are associated with security software:

    _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

  5. Attempts to terminate the following processes that are associated with other worms:

    winhlpp32.exe
    tftpd.exe
    dllhost.exe
    winppr32.exe
    mspatch.exe
    penis32.exe
    msblast.exe

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

    www.st.lib.keio.ac.jp
    www.lib.nthu.edu.tw
    www.stanford.edu
    www.xo.net
    www.utwente.nl
    www.schlund.net

  7. Runs the following network services:

    HTTP proxy on TCP port 63000
    HTTPS proxy on TCP port 63001
    SOCKS proxy on TCP port 30001
    FTP server on randomly chosen TCP port

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

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

  10. 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 (BID 8205).
    Exploits the Microsoft Windows Workstation Service Remote Buffer Overflow Vulnerability (BID 9011).

  11. To copy itself to network shares, the worm first attempts to enumerate the following remote administrative SMB shares.

    c$
    d$
    e$
    print$
    admin$

  12. The worm extracts possible user names, using NetUserEnum(), from discovered shares. It uses the harvested user names in conjunction with the following user name and password combinations, in a bid to authenticate to the discovered shared folders:

    User name:
    103015
    aaa
    abc
    Admin
    admin
    administrador
    Administrador
    Administrat
    Administrateur
    administrator
    Administrator
    admins
    asdf
    computer
    Convidado
    Coordinatore
    database
    Default
    Dell
    Gast
    Guest
    home
    Inviter
    kanri
    kanri-sha
    mary
    mgmt
    mysql
    OEM
    Ospite
    owner
    OWNER
    Owner
    qwer
    root
    server
    Standard
    student
    teacher
    temp
    Test
    user
    User
    Verwalter
    win
    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
    ASP
    baby
    backdoor
    BACKUP
    Box
    BOX
    box
    changeme
    CNN
    crash
    devil
    dude
    enable
    feds
    fish
    foobar
    fucked
    gay
    god
    godblessyou
    hax
    homework
    idiot
    ihavenopass
    Internet
    kids
    leet
    linux
    LOCAL
    Login
    lol
    love
    metal
    mybaby
    mybox
    mypass
    mypc
    noob
    oracle
    own
    owned
    pass
    PASSWD
    passwd
    password
    Password
    password123
    pat
    patrick
    penis
    PHP
    poiuytrewq
    porn
    private
    pussy
    pwd
    pwned
    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

  13. The worm copies itself and executes on any remote shares to which it successfully authenticates.

  14. Next, a Network job is scheduled to run the worm on the remote system.


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: Fergal Ladley

Discovered: April 24, 2004
Updated: February 13, 2007 12:21:57 PM
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.ADX. 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. Restart the computer in Safe mode or VGA mode.
  3. Reverse the changes made to the registry.
  4. Update the virus definitions.
  5. Run a full system scan and delete all the files detected as W32.Gaobot.ADX.
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 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.


3. 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 the value:

    "Video Process"="msconf.exe"

  5. Do one of the following:
    • Windows NT/2000/XP: Skip tp step h.
    • Windows 95/98/Me: 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:

    "Video Process"="msconf.exe"

  8. Navigate to the key:

    HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\

  9. Delete the key:

    Video Process

  10. Navigate to the key:

    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services

  11. Delete the subkey:

    Video Process

  12. Exit the Registry Editor.

  13. Restart the computer in Normal mode. For instructions, read the section on returning to Normal mode in the document, "How to start the computer in Safe Mode."

4. 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.



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.ADX, click Delete.


Writeup By: Fergal Ladley