W32.Kergez.A@mm

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Discovered: August 05, 2003
Updated: February 13, 2007 12:04:38 PM
Also Known As: I-Worm.Kergez [KAV]
Type: Worm
Systems Affected: Windows


W32.Kergez.A@mm is a mass-mailing worm that sends itself to all the email addresses that it finds in the following files:

  • Files with the *.asp, *.ht* extensions.
  • Files located in any of the directories specified in the registry key HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders.

The email messages will have the following characteristics:

Subject
: (One of the following)
  • Are you vulnerable to identity theft!
  • Protects against viruses, worms, Trojans & hackers.
  • Position Virus Percentage by Occurrence...
  • Microsoft Software Update Services
  • Saves money with 12 months of fast free antivirus updates
  • Cleans and removes infected files
  • Now its even easier to reduce spam
  • The easy, automatic way to keep your PC virus free
  • Protects against Trojans hackers
  • Kisacasi AntiVirusleri update etmeyi unutmayin ;)
  • Protects against viruses
  • InternetExplorer security patch
  • Online hackers
Attachment : (One of the following)
  • WinXP_Virus_Patch.exe
  • Virusun_Ensesine_Tokat.exe
  • Sophos_Patch.exe
  • Flood_Protect.exe
  • TrendMicro_Patch.exe
  • InternetWorm_Clean.exe
  • Fprot_Patch.exe
  • Security.exe
  • PantaAntivirus_Patch.exe
  • DoS_Protect.exe
  • DDoS_Kill.exe
  • Virus_Research.exe
  • Kaspersky_Patch.exe
  • BullGuard_Patch.exe
  • Norton_Patch.exe
  • Virus_Cleaner.exe
  • Virus_Guard.exe
  • Protect.exe
  • Virus_Hunter_II.exe
  • Internet_Speed.exe
  • Virus_Block.exe
  • Antivir.exe
The worm attempts to terminate the processes of various programs, including antivirus software.

W32.Kergez.A@mm is written in Microsoft Visual C++ and is UPX-packed.

Antivirus Protection Dates

  • Initial Rapid Release version August 06, 2003
  • Latest Rapid Release version August 08, 2016 revision 023
  • Initial Daily Certified version August 06, 2003
  • Latest Daily Certified version August 09, 2016 revision 001
  • Initial Weekly Certified release date August 06, 2003

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

Writeup By: Scott Gettis

Discovered: August 05, 2003
Updated: February 13, 2007 12:04:38 PM
Also Known As: I-Worm.Kergez [KAV]
Type: Worm
Systems Affected: Windows


When W32.Kergez.A@mm runs, it may perform some of the following actions:

  1. Copies itself to the %Windir% folder as Systray_.Exe.

    NOTE: %Windir% is a variable. The worm locates the Windows installation folder (by default, this is C:\Windows or C:\Winnt) and copies itself to that location.

  2. Adds the value:

    "Systray"="%windir%\Systray_.Exe"

    to the registry key:

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run

    so that the worm runs when you start Windows.

  3. Adds the value:

    "Cekirge"= <path to worm>

    to the registry key:

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\
    RunServices

  4. Drops a VBS script named Uslu_cekirge.vbs. This script creates a backdoor server named Cerkirge.exe, and then executes it. When this file is run, it copies itself to %System%\cekirge.scr and installs itself by adding the line:

    run=%System%\cekirge.scr

    to the %Windir%\Win.ini file.

    Note: These files are detected as Backdoor.Kergez.

  5. Attempts to terminate the following processes:
    • AVXGUI.EXE
    • AVPUPD.EXE
    • AVGSCAN.EXE
    • AVG.EXE
    • AVGW.EXE
    • AVXSCH.EXE
    • MGUI.EXE
    • FP-WIN.EXE
    • REGEDIT.EXE
    • BLACKICE.EXE
    • F-PROT.EXE
    • PAVSCHED.EXE
    • NMAIN.EXE
    • NAVW32.EXE
    • AVPM.EXE
    • MSCONFIG.EXE
    • AVP32.EXE
    • ZONEALARM.EXE
    • NAVAPW32.EXE
    • Firewall
    • Alarm
    • Secure
    • F-Prot
    • Clean
    • Guard
    • Panda
    • McAfee
    • Anti
    • Kaspersky
    • Norton
    • Check

  6. Sends itself to all the email addresses it finds in the following files:
    • Files with the *.asp, *.ht* extensions.
    • Files located in any of the directories specified in the registry key HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders.
    The email messages will have the following characteristics:

    Subject: (One of the following)
    • Are you vulnerable to identity theft!
    • Protects against viruses, worms, Trojans & hackers.
    • Position Virus Percentage by Occurrence...
    • Microsoft Software Update Services
    • Saves money with 12 months of fast free antivirus updates
    • Cleans and removes infected files
    • Now its even easier to reduce spam
    • The easy, automatic way to keep your PC virus free
    • Protects against Trojans hackers
    • Kisacasi AntiVirusleri update etmeyi unutmayin ;)
    • Protects against viruses
    • InternetExplorer security patch
    • Online hackers

    Body: (One of the following)
    • WARNING! Sophos: The update includes an array of new functions and improvements: ...
    • WARNING! Norton Antivirus: Object scanning optimization for improved performance Additional functionality for checking files compressed...
    • WARNING! Kaspersky Labs announces the regularly scheduled release of the Kaspersky Anti-Virus cumulative database update.
    • WARNING! The percentage shown represents the percentage of registered incidences. Position Virus Percentage by Occurrence...
    • WARNING! Get the ultimate in protection with our newly updated Junk Mail Filter!
    • WARNING! Especially over high-speed broadband connections, Internet hackers and identity thieves feast on unguarded PC connections (maybe yours) to steal passwords, credit card numbers and personal ID. Even turn your machine into a zombie to attack others.
    • WARNING! Be safe, be smart! Never surf the Net without a Personal Firewall Plus barrier between your hard drive and hostile cyber traffic.
    • WARNING! Online hackers know more than 2500 ways to break into naked unprotected PC systems.In seconds they steal private files credit card statements tax records passwords even Social Security Numbers
    • WARNING!Microsoft Software Update Services is designed to greatly simplify the process of keeping Windows-based systems up-to-date with the latest critical updates.SUS enables administrators to quickly and reliably deploy critical updates to their Windows 2000-based servers and Windows 2003-based servers as well as desktop computers running Windows 2000 Professional or Windows XP Professional.
    • WARNING!Are you vulnerable to identity theft!

    Attachment: (One of the following)
    • WinXP_Virus_Patch.exe
    • Virusun_Ensesine_Tokat.exe
    • Sophos_Patch.exe
    • Flood_Protect.exe
    • TrendMicro_Patch.exe
    • InternetWorm_Clean.exe
    • Fprot_Patch.exe
    • Security.exe
    • PantaAntivirus_Patch.exe
    • DoS_Protect.exe
    • DDoS_Kill.exe
    • Virus_Research.exe
    • Kaspersky_Patch.exe
    • BullGuard_Patch.exe
    • Norton_Patch.exe
    • Virus_Cleaner.exe
    • Virus_Guard.exe
    • Protect.exe
    • Virus_Hunter_II
    • Internet_Speed.exe
    • Virus_Block.exe
    • Antivir.exe



Recommendations

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: Scott Gettis

Discovered: August 05, 2003
Updated: February 13, 2007 12:04:38 PM
Also Known As: I-Worm.Kergez [KAV]
Type: Worm
Systems Affected: Windows


The following instructions pertain to all current and recent Symantec antivirus products, including the Symantec AntiVirus and Norton AntiVirus product lines.

  1. Disable System Restore (Windows Me/XP).
  2. Update the virus definitions.
  3. Run a full system scan and delete all the files detected as W32.Kergez.A@mm.
  4. Edit the Win.ini file (Windows 9x/Me).
  5. Reverse the changes made to the Registry.

For specific details on each of these steps, read the following instructions.

1. Disabling System Restore (Windows Me/XP)
If you are running Windows Me or Windows XP, we recommend that you temporarily turn off System Restore. Windows Me/XP uses this feature, which is enabled by default, to restore the files on your computer in case they become damaged. If a virus, worm, or Trojan infects a computer, System Restore may back up the virus, worm, or Trojan on the computer.

Windows prevents outside programs, including antivirus programs, from modifying System Restore. Therefore, antivirus programs or tools cannot remove threats in the System Restore folder. As a result, System Restore has the potential of restoring an infected file on your computer, even after you have cleaned the infected files from all the other locations.

Also, a virus scan may detect a threat in the System Restore folder even though you have removed the threat.

For instructions on how to turn off System Restore, read your Windows documentation, or one of the following articles:
For additional information, and an alternative to disabling Windows Me System Restore, see the Microsoft Knowledge Base article, "Antivirus Tools Cannot Clean Infected Files in the _Restore Folder ," Article ID: Q263455.

2. Updating the virus definitions
Symantec Security Response fully tests all the virus definitions for quality assurance before they are posted to our servers. There are two ways to obtain the most recent virus definitions:
  • Running LiveUpdate, which is the easiest way to obtain virus definitions: These virus definitions are posted to the LiveUpdate servers once each week (usually on Wednesdays), unless there is a major virus outbreak. To determine whether definitions for this threat are available by LiveUpdate, refer to the Virus Definitions (LiveUpdate).
  • Downloading the definitions using the Intelligent Updater: The Intelligent Updater virus definitions are posted on U.S. business days (Monday through Friday). You should download the definitions from the Symantec Security Response Web site and manually install them. To determine whether definitions for this threat are available by the Intelligent Updater, refer to the Virus Definitions (Intelligent Updater).

    The Intelligent Updater virus definitions are available: Read "How to update virus definition files using the Intelligent Updater" for detailed instructions.

3. Scanning for and deleting the infected files
  1. Start your Symantec antivirus program and make sure that it is configured to scan all the files.
  2. Run a full system scan.
  3. If any files are detected as infected with W32.Kergez.A@mm, click Delete.
4. Editing the Win.ini file (Windows 9x/Me)
If you are running Windows 95/98/Me, follow these steps:
  1. The function you perform depends on your operating system:
    • Windows 95/98: Go to step II.
    • Windows Me: If you are running Windows Me, the Windows Me file-protection process may have made a backup copy of the Win.ini file that you need to edit. If this backup copy exists, it will be in the C:\Windows\Recent folder. Symantec recommends that you delete this file before continuing with the steps in this section. To do this:
      1. Start Windows Explorer.
      2. Browse to and select the C:\Windows\Recent folder.
      3. In the right pane, select the Win.ini file and delete it. The Win.ini file will be regenerated when you save your changes to it in step VI.
  2. Click Start, and then click Run.
  3. Type the following, and then click OK.

    edit c:\windows\win.ini

    (The MS-DOS Editor opens.)

    NOTE: If Windows is installed in a different location, make the appropriate path substitution.

  4. In the [windows] section of the file, look for a line similar to:

    run = %system%\cekirge.scr

  5. If this line exists, delete everything to the right of =

    When you are done, it should look like:

    run =

  6. Click File, and then click Save.
  7. Click File, and then click Exit.
5. Reversing the changes made to the registry

CAUTION : Symantec strongly recommends that you back up the registry before making any changes to it. Incorrect changes to the registry can result in permanent data loss or corrupted files. Modify the specified keys only. Read the document, "How to make a backup of the Windows registry ," for instructions.
  1. Click Start, and then click Run. (The Run dialog box appears.)
  2. Type regedit

    Then click OK. (The Registry Editor opens.)

  3. Navigate to the key:

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run

  4. In the right pane, delete the value:

    "Systray"="%Windir%\Systray_.Exe"

  5. Navigate to the key:

    HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\RunServices

  6. In the right pane, delete the value:

    "Cekirge"= <path to worm>

  7. Exit the Registry Editor.


Writeup By: Scott Gettis