W32.HLLW.Amazex

SUMMARY

W32.HLLW.Amazex is a worm that attempts to spread across the KaZaA file-sharing network. It disguises itself as a pornographic-related program to trick users into downloading and opening it. W32.HLLW.Amazex is a native Visual Basic application.

Protection

• Virus Definitions (LiveUpdate™ Weekly) November 13, 2002
• Virus Definitions (Intelligent Updater) November 12, 2002

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
• Modifies Files: Modifies the registry.

Distribution

• Distribution Level: Low
• Shared Drives: Copies itself to the KaZaA shared folder.

TECHNICAL DETAILS

When W32.HLLW.Amazex runs, it performs the following actions:

Depending on random factors, it displays some of these messages:

• Alana by Xenopyre
• Critical Error in module FFFF:6578
• Your license has expired!
• Illegal module in KERNEL32.DLL
• SEXVIEWER32.DLL not found. Critical Error

The worm copies itself as more than one hundred files into the root folder of the drive from which it is running. The file names are constructed using combinations of the following strings:

• Boy
• Girl
• preteens
• AVP
• Norton Antivirus
• programs
• McAfee
• Downloader
• Prostye
• Memority Report
• Bioware downloader
• Card Generator
• Russian sex
• sex
• illegal
• crack
• serial
• key generator
• a group programs
• Antivirus
• sex confessions
• downloader
• films downloader
• party
• in bed
• brutal
• russian girls
• black girls
• oriental chicks
• britney!
• free
  

It also it attempts to copy itself as %system%Services.exe.

NOTES:

• %system% is a variable. The worm locates the System folder and attempts to copy the file to that location. By default this is C:WindowsSystem (Windows 95/98/Me), C:WinntSystem32 (Windows NT/2000), or C:WindowsSystem32 (Windows XP).
• If the operating system is Windows NT/2000/XP, the file %system%Services.exe (which is a legitimate Windows file that already exists on these systems) may not be rewritten because it is locked by the system.

The worm attempts to retrieve some of the system settings and information, including email addresses from the address book. The collected data might be dropped into these files:

• %system%Win32Sys.vxd
• %system%Win32Dls.vxd
• %system%Win32XXX.vxd

It then submits these files to a hacker. These files are not malicious, and Symantec antivirus products should not detect them.

The worm creates the value

Alana    %system%services.exe

in the registry key

HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindowsCurrentVersionRun

so that the worm runs when you start or restart Windows. (The worm runs only if the operating system is Windows 95/98/Me.)

Also, under the Windows 95/98/Me, the worm registers itself as a service process, so that it continues to run after you log off. In this case, W32.HLLW.Amazex closes only when the system is shut down.

The worm contains code that can copy itself into the KaZaA shared folder.

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

NOTE: These instructions are for all current and recent Symantec antivirus products, including the Symantec AntiVirus and Norton AntiVirus product lines.

1. Update the virus definitions
2. Run a full system scan, and delete all files that are detected as W32.HLLW.Amazex.
3. Delete the value
   
   Alana    %system%services.exe
   
   from the registry key
   
   HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindowsCurrentVersionRun
   

For details on how to do this, read the following instructions.

To update the virus definitions:
All virus definitions receive full quality assurance testing by Symantec Security Response before being posted to our servers. There are two ways to obtain the most recent virus definitions:

• Run LiveUpdate, which is the easiest way to obtain virus definitions. These virus definitions are posted to the LiveUpdate servers once 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 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.

To scan for and delete the infected files:

1. Start your Symantec antivirus program, and make sure that it is configured to scan all files.
   • Norton AntiVirus consumer products: Read the document How to configure Norton AntiVirus to scan all files.
   • Symantec enterprise antivirus products: Read the document How to verify a Symantec Corporate antivirus product is set to scan All Files.
2. Run a full system scan.
3. If any files are detected as infected with W32.HLLW.Amazex, click Delete.

To delete the value from the registry:

CAUTION: Symantec strongly recommends that you back up the registry before you make any changes to it. Incorrect changes to the registry can result in permanent data loss or corrupted files. Modify only the keys that are specified. Read the document How to make a backup of the Windows registry for instructions.

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 key
   
   HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindowsCurrentVersionRun
   
4. In the right pane, delete the value
   
   Alana    %system%services.exe
   
5. Exit the Registry Editor.