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Discovered: August 29, 2002
Updated: February 13, 2007 11:52:49 AM
Type: Worm
Systems Affected: Windows

W32.HLLW.Icasur is a worm that copies itself to the shared folders of the KaZaA file-sharing program. Several variants have been found. All variants are written in the Microsoft Visual Basic programming language and may be compressed with UPX. The worm disguises itself as movies, games, porno-related programs, or as software files to trick KaZaA users into downloading the program and opening it. Some of the possible file names are:

  • EuRoSuCks ScreenSaver.scr
  • Norton AntiVirus-FullInstall.exe
  • KAV40UPDT ScreenSaver.scr
  • KAV40-Full-Update!.exe

Antivirus Protection Dates

  • Initial Rapid Release version August 29, 2002
  • Latest Rapid Release version September 28, 2010 revision 054
  • Initial Daily Certified version August 29, 2002
  • Latest Daily Certified version September 28, 2010 revision 036
  • Initial Weekly Certified release date September 04, 2002

Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

Writeup By: Yana Liu

Discovered: August 29, 2002
Updated: February 13, 2007 11:52:49 AM
Type: Worm
Systems Affected: Windows

When W32.HLLW.Icasur runs, it does the following:

It copies itself to the root of drive C. The file name may vary, depending on the variant. Here are some samples:

  • C:\KMD_en.exe.
  • C:\Dogs!!.exe
  • C:\LDiana.exe
  • C:\EngSSL.exe
  • C:\AVP-CR.exe
  • C:\Loader.exe

It copies itself to one of the following folders, depending on the version of Windows:
  • C:\Windows\All Users\Start Menu\Programs\Startup
  • C:\Documents and Settings\All Users\Start Menu\Programs\Startup

The file name that it uses varies from version to version. Here are several examples:
  • EuRo.exe
  • Dogs.exe
  • LDD.exe
  • Ssl.exe
  • Avp.exe
  • Load.exe

It searches for KaZaA shared folders by using a registry key. If it finds a KaZaA shared folder, it copies itself to that location. The file name is chosen from the list that the worm carries. Here are some examples:
  • EuRoSuCks ScreenSaver.scr
  • Norton AntiVirus-FullInstall.exe
  • Deplhi-FullInstall.exe
  • HardCore Cum!!!.exe
  • Sum41-FatLip.exe
  • Windows2000-FullInstall.exe
  • Porn.exe
  • StarWars.exe


Symantec Security Response encourages all users and administrators to adhere to the following basic security "best practices":

  • Use a firewall to block all incoming connections from the Internet to services that should not be publicly available. By default, you should deny all incoming connections and only allow services you explicitly want to offer to the outside world.
  • 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.
  • Ensure that programs and users of the computer use the lowest level of privileges necessary to complete a task. When prompted for a root or UAC password, ensure that the program asking for administration-level access is a legitimate application.
  • Disable AutoPlay to prevent the automatic launching of executable files on network and removable drives, and disconnect the drives when not required. If write access is not required, enable read-only mode if the option is available.
  • Turn off file sharing if not needed. If file sharing is required, use ACLs and password protection to limit access. Disable anonymous access to shared folders. Grant access only to user accounts with strong passwords to folders that must be shared.
  • Turn off and remove unnecessary services. By default, many operating systems install auxiliary services that are not critical. These services are avenues of attack. If they are removed, threats have less avenues of attack.
  • If a 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.
  • Configure your email server to block or remove email that contains file attachments that are commonly used to spread threats, such as .vbs, .bat, .exe, .pif and .scr files.
  • Isolate compromised computers quickly to prevent threats from spreading further. 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.
  • If Bluetooth is not required for mobile devices, it should be turned off. If you require its use, ensure that the device's visibility is set to "Hidden" so that it cannot be scanned by other Bluetooth devices. If device pairing must be used, ensure that all devices are set to "Unauthorized", requiring authorization for each connection request. Do not accept applications that are unsigned or sent from unknown sources.
  • For further information on the terms used in this document, please refer to the Security Response glossary.

Writeup By: Yana Liu

Discovered: August 29, 2002
Updated: February 13, 2007 11:52:49 AM
Type: Worm
Systems Affected: Windows

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

Update the virus definitions, run a full system scan, and delete all files that are detected as W32.HLLW.Icasur. For details on how to do this, read the following instructions.

To scan for and delete the infected files:

  1. Obtain the most recent virus definitions. There are two ways to do this:
    • Run LiveUpdate, which 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.
  2. Start your Symantec antivirus program, and make sure that it is configured to scan all files.
  3. Run a full system scan.
  4. If any files are detected as infected with W32.HLLW.Icasur, click Delete.

Writeup By: Yana Liu