SymbOS.Commwarrior.A

SymbOS.Commwarrior.A is a worm that replicates on Series 60 phones. It attempts to spread using Multimedia Messaging Service (MMS) and Bluetooth as a randomly named .sis file. If it is the first hour of the 14th of any month, the threat resets the device.

Technical Details

When SymbOS.Commwarrior.A arrives at a target device, it may perform the following actions:

Creates the following files on the phone:

\system\updates\commwarrior.exe
\system\updates\commrec.mdl
\system\apps\commwarrior\commwarrior.exe
\system\apps\commwarrior\commrec.mdl
\system\recogs\commrec.mdl

Rebuilds an .sis file from the above files into the following location:

\system\updates\commw.sis

Searches for Bluetooth-enabled devices and attempts to send a randomly named copy of the .sis file to all devices that it finds.

Randomly chooses a phone number from the device's phonebook and sends an MMS message containing the commw.sis file as an attachment. The MIME type of the attachment is application/vnd.symbian.install.

The MMS messages have the following characteristics:

Subject: Norton AntiVirus
Message: Released now for mobile, install it!
Subject: 3DGame
Message: 3DGame from me. It is FREE !
Subject: 3DNow!
Message: 3DNow!(tm) mobile emulator for *GAMES*.
Subject: Audio driver
Message: Live3D driver with polyphonic virtual speakers!
Subject: CheckDisk
Message: *FREE* CheckDisk for SymbianOS released!MobiComm
Subject: Desktop manager
Message: Official Symbian desctop manager.
Subject: Display driver
Message: Real True Color mobile display driver!
Subject: Dr.Web
Message: New Dr.Web antivirus for Symbian OS. Try it!
Subject: Free SEX!
Message: Free *SEX* software for you!
Subject: Happy Birthday!
Message: Happy Birthday! It is present for you!
Subject: Internet Accelerator
Message: Internet accelerator, SSL security update #7.
Subject: Internet Cracker
Message: It is *EASY* to *CRACK* provider accounts!
Subject: MS-DOS
Message: MS-DOS emulator for SymbvianOS. Nokia series 60 only. Try it!
Subject: MatrixRemover
Message: Matrix has you. Remove matrix!
Subject: Nokia ringtoner
Message: Nokia RingtoneManager for all models.
Subject: PocketPCemu
Message: PocketPC *REAL* emulator for Symbvian OS! Nokia only.
Subject: Porno images
Message: Porno images collection with nice viewer!
Subject: PowerSave Inspector
Message: Save you battery and *MONEY*!
Subject: Security update #12
Message: Significant security update. See www.symbian.com
Subject: Symbian security update
Message: See security news at www.symbian.com
Subject: SymbianOS update
Message: OS service pack #1 from Symbian inc.
Subject: Virtual SEX
Message: Virtual SEX mobile engine from Russian hackers!
Subject: WWW Cracker
Message: Helps to *CRACK* WWW sites like hotmail.com

If it is the first hour of the 14th of any month, the threat resets the device.

Recommendations

Turn off and remove unneeded services. By default, many operating systems install auxiliary services that are not critical, such as an FTP server, telnet, and a Web server. These services are avenues of attack. If they are removed, blended threats have less avenues of attack and you have fewer services to maintain through patch updates.
If a blended 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 (for example, all Windows-based computers should have the current Service Pack installed.). Additionally, please apply any security updates that are mentioned in this writeup, in trusted Security Bulletins, or on vendor Web sites.
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.
Configure your email server to block or remove email that contains file attachments that are commonly used to spread viruses, such as .vbs, .bat, .exe, .pif and .scr files.
Isolate infected computers quickly to prevent further compromising your organization. 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.

Removal Instructions :

To remove SymbOS.Commwarrior.A:

Install a file manager program on the phone.
Enable the option to view the files in the system directory.
Search the drives, A through Y, for the \system\apps\commwarrior directory.
Delete the files commwarrior.exe and commrec.mdl.
Go to the \system\updates\commwarrior directory.
Delete the files commwarrior.exe, commrec.mdl, and commw.sis.
Go to the \system\recogs directory.
Delete the file commrec.mdl.

Additional information

Symantec recommends the following to protect against this threat:

• If Bluetooth is not required, it should be turned off.
• If you require the use of Bluetooth, ensure that the device's visibility setting is set to "Hidden" so that it can not be scanned by other Bluetooth devices.
• Avoid use of device pairing. If it must be used, ensure that all paired devices are set to "Unauthorized". This requires each connection request to be authorized by the user.
• Do not accept unsigned applications (no digital signature) or applications sent from unknown sources. Be absolutely sure of the origin of the application before accepting it.

Symantec offers a security solution for Symbian known as Symantec Client Security for Nokia Communicators. This product can be downloaded via the Nokia 9500/9300 web browser or from a PC. Symantec will never send unsolicited messages regarding one of our products. For additional information please see http://www.symantec.com/smallbiz/nok.

More info visite http://securityresponse.symantec.com/avcenter/venc/data/symbos.commwarrior.b.html

Caution : we dont take any resposbilty if your phone is damamged, Experiment at your own risk.