W32.Excuse.Worm@m

SUMMARY

W32.Excuse.Worm@m is an email worm that sends itself to a random address in the Windows Address Book that ends in .com (for example joe@user.com).

Protection

• Virus Definitions (Intelligent Updater) May 16, 2001

Threat Assessment

Wild

• Wild Level: Low
• Number of Infections: 0 - 49
• Number of Sites: 0 - 2
• Geographical Distribution: Low
• Threat Containment: Easy
• Removal: Easy

Damage

• Damage Level: Low

Distribution

• Distribution Level: Low

TECHNICAL DETAILS

When W32.Excuse.Worm@m is first executed, it copies itself into the Windows folder as W32_1st.exe.
Next, the value:

XRF   <path>w32_1st.exe

is added to the registry key:

HKEY_LOCAL_MACHINESoftwareMicrosoft
WindowsCurrentVersionRun

The worm will then retrieve the file name of the Windows Address Book from the registry, choose a random position within the file, and search for an email address that ends in .com. The following mail is sent to that address:

From: New_FamouS_GirLs (The_Hanged@jazzfree.com)
To: Sex_Spam_,_ExcusE_Me
Sent: 2001/03/03 15:00
Subject: BriTneY_vs_AguiLerA
Message: BritneY, AguiLEra, Paulina & Much More From ... www.tremendus.com
Attachment: BriTneYvsAguiLerA.exe

If the worm is executed at any time during the year 2002, the following message box will be displayed after the mail is sent:



If the worm is executed at any time during the month of September in any year, the following mail will be sent to kriptopolis@kriptopolis.com:

From: A.S.N. (The_Hanged@hotmail.com)
To: W32_1st (kriptopolis@kriptopolis.com)
Sent: 2001/09/03 02:00
Subject: MientrasVosotrosHablaisOtrosAbrenCodigos
Message: AlguienDeberiaPublicarAlgunTrabajoSerioSobreSecrafoniaDe R.C.
Attachment: W32_1st.exe

Recommendations

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.

REMOVAL

To remove this worm, delete any files detected as W32.Excuse.Worm@m and undo the changes that it made to the registry.

To remove the worm:

1. Run LiveUpdate to ensure that you have the most recent virus definitions.
2. Start Norton AntiVirus and run a full system scan, making sure that NAV is configured to scan all files.
3. Delete any files detected as W32.Excuse.Worm@m

To edit the registry:

CAUTION: We strongly recommend that you back up the system registry before making any changes. Incorrect changes to the registry could result in permanent data loss or corrupted files. Please make sure you modify only the keys specified. Please see the document How to back up the Windows registry before proceeding.

1. Click Start, and click Run. The Run dialog box appears.
2. Type regedit and then click OK. The Registry Editor opens.
3. Navigate to the following key:
   
   HKEY_LOCAL_MACHINESoftware
   MicrosoftWindowsCurrentVersionRun
   
4. In the right pane, delete the following value:
   
   XRF
   
5. Click Registry, and then click Exit.