- 27 August 2001
- 13 February 2007
VBS.Emin.A@mm is a worm that creates a randomly named script file in a random folder, emails itself and a .doc file from the computer to all the addresses in the Microsoft Outlook address book, and then restarts the computer. The script file that it created then attempts to delete all files on drive C.
Antivirus Protection Dates
- Initial Rapid Release version 27 August 2001
- Latest Rapid Release version 28 September 2010 revision 054
- Initial Daily Certified version 27 August 2001
- Latest Daily Certified version 28 September 2010 revision 036
- Initial Weekly Certified release date pending
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.
When it is executed, this worm performs the following actions:
- The worm searches for a random folder on drive C.
- It creates a script file that uses that folder's name and the current time (in numeric format) as the file name, with the .js extension. Into this file it writes a short script that attempts to delete all files on drive C.
- It adds a value that refers to this newly created script file to the registry key
so that the script runs each time that Windows starts.
- It searches drive C for a file with a .doc extension.
- It checks for version information of the Microsoft Outlook program. If the version information exists, it uses the MAPI Personal Address Book to locate email addresses; otherwise, it uses the addresses from the MAPI Contacts folder.
- For each of the addresses that it finds, the worm sends an email using the following format:
Subject: <no subject> (The subject line actually contains the text "<no subject>")
Message: Some body (The message actually consists of the text "Some body")
Attachments: This worm sends two attachments:
- A copy of the worm itself as the file "Some very cool thing I made.js"
- A copy of the randomly selected .doc file as the file "This 1 is very cool too.doc"
- It restarts the computer so that the dropped script file--which tries to delete all files on drive C--will run.
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.
To remove this worm, delete all files that are detected as VBS.Emin.A@mm and delete the entry that it made in the registry.
NOTE: If the worm has executed and has deleted the contents of drive C, you will have to reinstall the operating system and all software installed on that drive, and restore data from a recent backup.
To remove the worm:
- Run LiveUpdate to make sure that you have the most recent virus definitions.
- Start Norton AntiVirus (NAV), and run a full system scan. Be sure that NAV is configured to scan all files.
- Delete all files that are detected as VBS.Emin.A@mm.
To edit the registry:
CAUTION : We strongly recommend that you back up the system registry before you make any changes. Incorrect changes to the registry could result in permanent data loss or corrupted files. Please make sure that you modify only the keys that are specified. Please see the document How to back up the Windows registry before you proceed.
- Click Start, and click Run. The Run dialog box appears.
- Type regedit and then click OK. The Registry Editor opens.
- Navigate to the following key:
- In the right pane, look for a value that refers to a file that uses the following format:
<name of a folder that exists on drive C> <numbers>.js
- Select this value, and then press Delete.
- Exit the Registry Editor.