VBS.Timofonica

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Discovered: June 06, 2000
Updated: February 13, 2007 11:54:58 AM
Also Known As: I-Worm.Timofonica, VBS/Timofonica, VBS/Timo-A
Type: Worm


This is a Visual BASIC Script worm which is currently detected by Norton AntiVirus as VBS.NewLove.A. This detection was confirmed using the May 30 definitions. The worm replicates by mailing itself using Microsoft Outlook.

Antivirus Protection Dates

  • Initial Rapid Release version June 07, 2000
  • Latest Rapid Release version August 08, 2016 revision 023
  • Initial Daily Certified version June 07, 2000
  • Latest Daily Certified version August 09, 2016 revision 001

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

Writeup By: Brian Ewell

Discovered: June 06, 2000
Updated: February 13, 2007 11:54:58 AM
Also Known As: I-Worm.Timofonica, VBS/Timofonica, VBS/Timo-A
Type: Worm


VBS.Timofonica is a script worm. It is written in the Visual BASIC language and makes use of the Windows Scripting Host to execute its content. This worm propagates by email through the Outlook client.

When launched, the script determines if it has already infected the current system. In a system that has been infected, the registry key
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Timofonica
will exist. If this key is present the script will exit without performing any further actions.

On a system that has not been previously infected the script performs the following functions:

  • The script creates the file Cmos.com in the Windows system folder and adds the following registry key:
    HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run\Cmos

    This Trojan is capable of corrupting the computer's CMOS and boot information. Cmos.com is executed when the computer restarts.
  • The script creates the Timofonica.txt text file in the root directory of drive C. This file contains a list of Web sites that are related to the message the worm's author is trying to spread.
  • The script uses Outlook to send itself to every address in the address book. The worm modifies the registry so that no copy of the outgoing message is saved.
  • For each entry in the address book, the script also sends a message to a subscriber of the movistar.net service. The address to which the message is sent consists of a randomly chosen prefix from a known list of prefixes (609, 619, 629, 630, 639, 646, 649 or 696) and a randomly generated six-digit number.
  • The worm modifies the registry so that any further attempts to execute a .vbs file result in the system opening up Notepad to display the C:\Timofonica.txt file.


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: Brian Ewell

Discovered: June 06, 2000
Updated: February 13, 2007 11:54:58 AM
Also Known As: I-Worm.Timofonica, VBS/Timofonica, VBS/Timo-A
Type: Worm


You must complete the following steps to manually remove this worm from the computer:

  1. Search the computer for files named Timofonica.txt, and delete them. The default locations for these files is C:\.
  2. Search the computer for Cmos.com, and delete it. This file should be in your \Windows\System folder.
  3. Run Regedit.exe to delete the following registry keys:
    HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run\Cmos
    HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Timofonica

  4. Navigate to the following key:
    HKEY_LOCAL_MACHINE\Software\Classes\VBSFile\Shell\Open\Command
  5. Set the key to the following value:
    C:\WINDOWS\WScript.exe "%1" %*

    For clarity, the characters are quote, percent sign, numeral one, quote, space, percent sign, asterisk.
  6. Within Outlook, enable the option to save copies of messages into the Sent folder.


Writeup By: Brian Ewell