W32.Hobble.H@mm

SUMMARY

W32.Hobble.H@mm is a mass-mailing worm that replicates by email and attempts to spread across the KaZaA file-sharing network. It also attempts to terminate the processes of various security related programs.

W32.Hobble.H@mm is a .NET executable that is written in C# and runs only in the .NET Framework. The email message has the following characteristics:

Message Body: all we are saying, is give peace a chance. no to war and terrorism.

Attachment: Topeace.exe

Protection

• Virus Definitions (LiveUpdate™ Weekly) December 4, 2002
• Virus Definitions (Intelligent Updater) December 2, 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
• Large Scale E-mailing: Sends mail to all addresses found within files beginning with the extension .ht on the local computer.
• Compromises Security Settings: Attempts to terminate processes of various security programs.

Distribution

• Distribution Level: High
• Name of Attachment: Topeace.exe
• Shared Drives: Attempts to spread across the KaZaA file-sharing network.

TECHNICAL DETAILS

W32.Hobble.H@mm is a C# application that is compiled to MSIL. It runs only in the .NET Framework.

When W32.Hobble.H@mm runs, it performs the following actions:

It lists running processes and attempts to terminate the following processes:

• _Avp32
• _Avpcc
• _Avpm
• Ackwin32
• Anti-Trojan
• Apvxdwin
• Autodown
• Avconsol
• Ave32
• Avgctrl
• Avkserv
• Avnt
• Avp
• Avp32
• Avpcc
• Avpdos32
• Avpm
• Avptc32
• Avpupd
• Avsched32
• Avwin95
• Avwupd32
• Blackd
• Blackice
• Cfiadmin
• Cfiaudit
• Cfinet
• Cfinet32
• Claw95
• Claw95cf
• Cleaner
• Cleaner3
• Dvp95
• Dvp95_0
• Ecengine
• Esafe
• Espwatch,
• F-Agnt95
• Findviru
• Fprot
• F-Prot
• F-Prot95
• Fp-Win
• Frw
• F-Stopw
• Iamapp
• Iamserv
• Ibmasn
• Ibmavsp
• Icload95
• Icloadnt
• Icmon
• Icsupp95
• Icsuppnt
• Iface
• Iomon98
• Jedi
• Lockdown2000
• Lookout
• Luall
• Moolive
• Mpftray
• N32scanw
• Navapw32
• Navlu32
• Navnt
• Navw32
• Navwnt
• Nisum
• Nmain
• Normist
• Nupgrade
• Nvc95
• Outpost
• Padmin
• Pavcl
• Pavsched
• Pavw
• Pccwin98
• Pcfwallicon
• Persfw
• Rav7
• Rav7win
• Rescue,
• Safeweb
• Scan32
• Scan95
• Scanpm
• Scrscan
• Serv95
• Smc
• Sphinx
• Sweep95
• Tbscan
• Tca
• Tds2-98
• Tds2-Nt
• Vb6
• Vet95
• Vettray
• Vscan40
• Vsecomr,
• Vshwin32
• Vsstat
• Webscanx
• Wfindv32
• Zonealarm

The worm adds the value

Dir0     012345:<folder where the worm is located>

to the registry key

HKEY_CURRENT_USERSoftwareKazaaLocalContent

so that other KaZaA users can download the worm.

It then copies itself to the current folder as:

• Avril_lavigne.exe
• Brigadaocho.net.exe
• Drunken_pope_pics.exe
• Hitman2fulldownloader.exe
• How_to_get_chicks_on_your_bed.exe
• Scan.net.exe
• Shakira.exe
• Teach_yourself_c#_in_1_week.exe
• Teach_yourself_cobol.net_in_21_days.exe
• Tekken4_full_downloader.exe
• Visual_studio.net2003_key.exe

Next, W32.Hobble.H@mm inventories local files that have extensions which start with .ht, such as .htm and .html. It searches for mailto tags in these files and retrieves the email addresses. The worm sends itself to the retrieved addresses as the following email message:

Message Body: all we are saying, is give peace a chance. no to war and terrorism.

Attachment: Topeace.exe

Finally, the worm may display this message:

brigada ocho ::: "bringing the c# technology to the masses"
msil.mass by PerrunBoy ::: http:/ /vx.netlux.org/~b8

W32.Hobble.H@mm does not handle certain exceptions that it might throw. As a result, it may fail under certain circumstances.

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.Hobble.H@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 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.Hobble.H@mm, click Delete.