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| Symantec Security Response http://securityresponse.symantec.com |
W97M.Melissa.BG | 
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W97M.Melissa.BG is a Microsoft Word 97 macro virus that has a payload that deletes necessary system files. It also sends itself through email using Microsoft Outlook.
| Also Known As: | ResumeWorm, W97M.Resume.A |
| Type: | Worm |
| Infection Length: | 41,472 |
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- Payload:
- Large scale e-mailing: All addresses in the User's Address book using Microsoft Outlook
- Deletes files: C:\*.* C:\My Documents\*.* C:\WINDOWS\*.* C:\WINDOWS\SYSTEM\*.* C:\WINNT\*.* C:\WINNT\SYSTEM32\*.* Also A-Z:\*.*
- Degrades performance: May crash e-mail server
- Causes system instability: Deletes system files
- Subject of email: Resume - Janet Simons
- Name of attachment: RESUME1.DOC or Explorer.doc or NORMAL.DOT
- Size of attachment: 41,472
W97M.Melissa.BG a macro virus that has an unusual payload. When you open an infected document, the virus attempts to use Microsoft Outlook to email a copy of the document to everyone in the Microsoft Outlook address book.
The email has the following format:
Subject: Resume - Janet Simons
Message:
To: Director of Sales/Marketing,
Attached is my resume with a list of references contained within. Please feel free to call or email me if you have any further questions regarding my experience. I am looking forward to hearing from you.
Sincerely,
Janet Simons.
The virus also creates two copies of itself:
- C:\Data\Normal.dot
- C:\WINDOWS\Start Menu\Programs\StartUp\Explorer.doc
When you close the document the virus attempts to delete the following files:
- C:\*.*
- C:\My Documents\*.*
- C:\WINDOWS\*.*
- C:\WINDOWS\SYSTEM\*.*
- C:\WINNT\*.*
- C:\WINNT\SYSTEM32\*.*
- A:\*.*
- B:\*.*
- D:\*.*
- E:\*.*
- F:\*.*
- G:\*.*
- H:\*.*
- I:\*.*
- J:\*.*
- K:\*.*
- L:\*.*
- M:\*.*
- N:\*.*
- O:\*.*
- P:\*.*
- Q:\*.*
- R:\*.*
- S:\*.*
- T:\*.*
- U:\*.*
- V:\*.*
- W:\*.*
- X:\*.*
- Y:\*.*
- Z:\*.*
Symantec Security Response encourages all users and administrators to adhere to the following basic security "best practices":
- 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.
- Obtain the most recent virus definitions. There are two ways to do this:
- Run LiveUpdate. LiveUpdate is the easiest way to obtain virus definitions. These virus definitions have undergone full quality assurance testing by Symantec Security Response and are posted to the LiveUpdate servers one time each week (usually Wednesdays) unless there is a major virus outbreak. To determine whether definitions for this threat are available by LiveUpdate, look at the Virus Definitions (LiveUpdate) line at the top of this write-up.
- Download the definitions using the Intelligent Updater. Intelligent Updater virus definitions have undergone full quality assurance testing by Symantec Security Response. They are posted on U.S. business days (Monday through Friday). They must be downloaded from the Symantec Security Response Web site and installed manually. To determine whether definitions for this threat are available by the Intelligent Updater, look at the Virus Definitions (Intelligent Updater) line at the top of this write-up.
Intelligent Updater virus definitions are available here. For detailed instructions on how to download and install the Intelligent Updater virus definitions from the Symantec Security Response Web site, click here.
- Start Norton AntiVirus (NAV), and make sure that NAV is configured to scan all files. For instructions on how to do this, read the document How to configure Norton AntiVirus to scan all files.
- Run a full system scan.
- If any files are detected as infected by W97M.Melissa.BG, click Repair. (Delete the virus files C:\Data\Normal.dot and C:\WINDOWS\Start Menu\Programs\StartUp\Explorer.doc.)
Revision History:
- April 4, 2002: Downgraded to Category 2
Write-up by: Douglas Knowles