W32.Kitro.E.Worm

When W32.Kitro.E.Worm runs, it does the following:

It displays this fake error message:



It creates multiple copies of itself using the following file names:

• %windir%\PostalDeAmistad.pif
• %windir%\AuToDeTeRmInAzIon.Doc.pif
• %windir%\List.txt.by.Microsoft.com
• %windir%\Facturas556.XLS.pif
• %windir%\EnNavarras.pif
• %windir%\YaNoPuedoTener$$$$$.DOC.pif
• %windir%\Cajerosautomaticos!!!.DOC.pif
• C:\ .exe
• C:\AVP40Crack.exe
• C:\ResidentEvil-Crack.exe
• C:\AVP-SpanishPatch.exe
• C:\PandaAllCracks.exe
• C:\MessengerSkins29.exe
• C:\HackTools.exe
• C:\MP3EncoderDecoder58.exe
• C:\GameCube-FreeEmulator.exe
• C:\PSX2-Emulator.exe
• C:\X-Box_Emulator.exe
• C:\PSXEmulator_Full.exe
• C:\CounterStrikeMoreServers.exe
• C:\Jedi2-FullCrack.exe
• C:\W98ToXpActualization.exe
• C:\WindowsXP-Serials.exe
• C:\GamesPSX2Emulator.exe
• C:\CopyPSXgamesV12.exe

NOTE: %windir% is a variable. The worm locates the \Windows folder (by default this is C:\Windows or C:\Winnt) and copies itself to that location.

It attempts to delete the following antivirus software files:

• C:\Archiv~1\Perav\Pav.dll
• C:\Archiv~1\Perav\Per.dll
• C:\Program Files\Perav\Pav.dll
• C:\Program Files\Perav\Per.dll
• %windir%\Pav.exe
• %windir%\Bases\Avp.set
• %windir%\System\Vshield.vxd
• %windir%\System32\Vshield.vxd
• %windir%\Vshield.vxd

Next, W32.Kitro.E.Worm creates or alters the value:

Folder

in the registry key

HKEY_LOCAL_MACHINE\SOFTWARE\KasperskyLab\SharedFiles

and the values

PAV.EXE
Zonavirus

in the registry key

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run

For every file in the root of drive C, W32.Kitro.E.Worm attempts to overwrite it with itself. The worm uses the original file names, but appends the string " .exe" to them.

It drops the file BanderaNegra.vbs in the root of drive C. This file is detected as VBS.Kitro@mm.

To force itself to run when you start Windows, the worm creates the following values

BNexe (one of the dropped W32.Kitro.E.Worm files)
KAZAAkCuF (one of the dropped W32.Kitro.E.Worm files)

in the registry key

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run

Next, W32.Kitro.E.Worm attempts to replicate by sending the viral email to all .NET Messenger contacts using the mail.hotmail.com SMTP server. It also attempts to replicate through the KaZaA peer-to-peer network. It copies itself to the KaZaA share, thus making itself available for other KaZaA users to download.

The viral email message that the worm constructs may have various characteristics. Some examples are:

Subject: Te han enviado una postal.
Message: Postales NetWork (c)1999-2002.
Attachment: PostalDeAmistad.pif

Subject: Leelo y reenvialo a quienes aprecias.
Message: Si lo que expone este documento es lo que sientes, envialo a tus amigos, algun sue±o se hara realidad.
Attachment: AuToDeTeRmInAzIon.Doc.pif

Subject: This is the last problem.
Message: I send the list of problems now, so that you do not make case to the lies bye.
Attachment: List.txt.by.Microsoft.com

Subject: Para los amigos
Message: Aqui adjunto las Facturas que nos ha pedido, ruego que nos envie lo que dentro del documento se especifica, Saludos.
Attachment: Facturas556.XLS.pif

Subject: Fw: Enviame tu foto.
Message: bueno, aqui esta la foto queme has pedido cuando viaje al pais vasco en verano!ja.
Attachment: EnNavarras.pif

Subject: Es posible que nos roben el dinero!!!.
Message: lee el documento y veras que puede ser verdad, luego enviaselo a tus amigos para que no les suceda eso.
Attachment: YaNoPuedoTener$$$$$.DOC.pif

Subject: Banks vulnerabilitie
Message: si, ahora nos pueden espiar la cuenta, te envio el documento donde dice que es lo que se debe hacer para arreglarlo, arreglalo lo antes posible.
Attachment: Cajerosautomaticos!!!.DOC.pif

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