W32.Hobble@mm

SUMMARY

W32.Hobble@mm is a worm that attempts to spread across the KaZaA file-sharing network. It has mass-mailing capabilities, and can send itself to the email addresses that it retrieves from the .htm and .html files that it finds in the Internet Explorer cache. W32.Hobble@mm is a Visual Basic application.

Protection

• Virus Definitions (LiveUpdate™ Weekly) September 25, 2002
• Virus Definitions (Intelligent Updater) September 24, 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

Distribution

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

TECHNICAL DETAILS

If the operating system is 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.Hobble@mm closes only when you shut down the computer.

To replicate across the KaZaA file-sharing network , the worm copies itself as these file names:

• WIN XPCrack.exe
• All GamesHack.exe
• ICQ Password Hack.exe
• HotMailHack.exe
• Unreal Tournament 3 FullDownloader.exe

into these folders (if they exist):

• C:KaZaAMy Shared Folder
• C:Program FilesKaZaAMy Shared Folder

The mass-mailing portion of the worm scans all .htm and .html files in the Internet Explorer cache and retrieves email addresses from mailto: links. The retrieved addresses are stored in a file named Email.txt, which the worm drops into the same folder. It then retrieves the user name, email address, and SMTP server and sends itself to the retrieved contacts in the following format:

Message Body: files for you - from <User name>
Subject: RE:
Attachment #1: (49,152 bytes)
The file name of the first attachment is randomly selected from the following list:

• I-Explorer7.0
• Morpheus_Update_Fix
• Kaza_Lite_Update_Fix
• Kaza_Fix
• Edonkey_Fix
• WinXP_Crack
• Symantec_KeyGen
• McAffea_KeyGen
• Flock_Update
• Bearshare_Fix
• New_Napster_Clone
• Pamela_Live_F***ing
• Beyond_FF11
• Final_Fantasy10
• Reboot
• Claudia_Schiffer
• FullSpeed
• Email Bomber
• FTP Cracker
• Hotmail Hacker Tool
• Anti 0190 Dialer
• WinMx Hack
• Britney Spears Nude
• Shakira Nude
• Jenifer Lopez Naked
• Ps2 Emulator
• Cube Emulator
• Ps2 Crack
• XBox Emulator
• Borland Delphi 6 Key
• Borland Delphi(all) Crack

The attached file has one the following extensions:

• .exe
• .pif
• .bat
• .scr

The attached file is a copy of the worm that was dropped into the same folder as the folder from which the worm was executed.

Attachment #2: (Random file size)
The file name of the second attachment is randomly selected from this list:

• Shakira Nude.theme
• BackstreetBoys.theme
• Goldfinger.theme
• Shrek.theme
• LordoftheRings.theme
• StarWars.theme
• MichelleBranch.theme
• TheHives.theme
• DrNo.theme
• JamesBond.theme
• NSync.theme
• AddamsFamily.theme
• SamuraiX.theme
• DragonballZ.theme
• Hackers.theme
• PlayboyCenterFolds.theme
• BritneySpearsNude.theme
• ChristinaAguilera.theme
• Energy.theme
• alcopaul.theme
• XXX.theme
• NicoleKidman***.theme
• CourtneyCoxNude.theme
• LearnVisualBasic.zip
• LearnVisualC.zip
• LearnVisualFoxPro.zip
• LearnPHP.zip
• LearnHTML.zip
• LearnKylix.zip
• SecretsOfMicrosoftdotNET.zip
• LearnCSharp.zip
• LearnVisualBasic.NET.zip
• CplusplusUnleashed.zip
• Hacking101.zip
• EroticStories.zip
• SecretsofLaoTse.zip
• Phreaking.zip
• CIASecrets.zip
• VirusWriting.zip
• TipsOnMakingYourPartnerWild.zip
• CreditCardNumbers.zip
• NewsweekSeptemberEditionCompressed.zip
• TroubleshootingyourComputer.zip
• CounterStrikeCheats.zip
• JokeForTheDay.zip
• MakeMillions.zip
• YouWantToBeAMillionaire.zip
• DisneyBedTimeStories.zip
• StephenKingUnreleasedNotes.zip
• NikolaTeslaNotes.zip
• SecretsOfAlbertEinstein.zip
• ThomasEdisonSecrets.zip
• AlexanderGrahamBellSecrets.zip
• HackSQLServersScript.bat
• HackIISServersScript.bat
• HackMozillaServersScript.bat
• HackHotmailScript.bat
• HackYahooScript.bat
• HackApacheServersScript.bat
• HackXBoxScript.bat
• HackPayPalScript.bat
• WindowsSourceCodeRedirect.bat
• RedirectMeToHollywood.bat
• Morpheus_Update_Fix.bat
• Kaza_Lite_Update_Fix.bat
• Kaza_Fix.bat
• Edonkey_Fix.bat
• WinXP_Crack.bat
• Symantec_KeyGen.bat
• McAffea_KeyGen.bat
• Flock_Update.bat
• Bearshare_Fix.bat
• New_Napster_Clone.bat
• Pamela_Live_***.bat
• Beyond_FF11.bat
• Final_Fantasy10.bat
• Reboot.bat
• Claudia_Schiffer.bat
• FullSpeed.bat
• Email Bomber.bat
• FTP Cracker.bat
• Hotmail Hacker Tool.bat
• Anti 0190 Dialer.bat
• WinMx Hack.bat
• Britney Spears Nude.bat

To generate a file for the second attachment, the worm performs the following actions:

• If the file name has the .zip extension, the worm downloads a zip utility from a Web site, drops it as Zippy.exe in the same folder, and runs it to produce the zipped copy of the worm.
• If the file name has the .theme or .bat extension, the worm attempts to produce a text file with the encoded worm body. When the worm runs, it is supposed to use the legitimate debug utility to drop the binary of the worm and then execute it. Due to bugs, the .theme or .bat files do not appear to be successfully produced.

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. Do one of the following:
   • Windows 95/98/Me: Restart the computer in Safe mode.
   • Windows NT/2000/XP: End the worm process.
3. Run a full system scan, and delete all files that are detected as W32.Hobble@mm.
   

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 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 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 restart the computer in Safe mode or end the worm process:
Windows 95/98/Me
Restart the computer in Safe mode. All Windows 32-bit operating systems, except for Windows NT, can be restarted in Safe mode. For instructions on how to do this, read the document How to start the computer in Safe Mode.

Windows NT/2000/XP
To end the worm process:

1. Press Ctrl+Alt+Delete one time.
2. Click Task Manager.
3. Click the Processes tab.
4. Double-click the Image Name column header to sort the processes alphabetically.
5. Scroll through the list, and look for Hobbit.exe or any of the file names that appear in the Technical Description section.
6. If you find the file, click it, and then click End Process.
7. Close the Task Manager.

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.Hobble@mm, click Delete.