Symantec Security Response - W32.Galil.C@mm © 1995-2003 Symantec Corporation. All rights reserved. Legal Notices Privacy Policy W32.Galil.C@mm Discovered on: September 28, 2003 Last Updated on: September 29, 2003 12:44:09 PM W32.Galil.C@mm is a mass-mailing worm that sends itself to the email addresses it finds in the files that have the .htm, .html, .eml, and .txt file extensions. The email will have a variable subject line and attachment name. The original sample received had a .scr file extension. This worm sends itself to all the contacts in the Microsoft Outlook Address Book and MSN messenger contact list, and it attempts to spread itself through the KaZaA file-sharing network. This threat is written in the Microsoft Visual Basic programming language and is compressed with UPX. Type: Worm Infection Length: 56,614 bytes, 20,992 bytes Systems Affected: Windows 2000, Windows 95, Windows 98, Windows Me, Windows NT, Windows Server 2003, Windows XP Systems Not Affected: DOS, Linux, Macintosh, OS/2, UNIX Virus Definitions (Intelligent Updater) * September 29, 2003 Virus Definitions (LiveUpdate™) ** October 01, 2003 *Intelligent Updater definitions are released daily, but require manual download and installation. Click here to download manually. **LiveUpdate virus definitions are usually released every Wednesday. Click here for instructions on using LiveUpdate. Wild: Number of infections: 0 - 49 Number of sites: 0 - 2 Geographical distribution: Low Threat containment: Easy Removal: Moderate Threat Metrics Wild: LowDamage: LowDistribution: High Damage Payload: Large scale e-mailing: Sends itself to the email addresses it finds from the files, .htm, .html, .eml, and .txt. It also sends itself to all the contacts in the Outlook address book and MSN messenger contact list. Distribution Subject of email: varies Name of attachment: varies (likely .exe, .pif, or .scr) Size of attachment: 56,614 bytes Shared drives: It also attempts to spread itself through the KaZaA file-sharing network. When W32.Galil.C@mm runs, it does the following: Copies itself as %System%2.sys. NOTE: %System% is a variable. The worm locates the System folder and copies itself to that location. By default, this is C:\Windows\System (Windows 95/98/Me), C:\Winnt\System32 (Windows NT/2000), or C:\Windows\System32 (Windows XP). Creates the following files: %Temp%\Explore.exe, which is 20,992 bytes in length. The file attributes are Hidden, Read-only, and System. %Temp%\A.exe, which is 9,216 bytes in length. %Temp%\SMTP.ocx, which is 25,737 bytes in length. NOTES: SMTP.ocx does not contain viral code, and therefore Symantec antivirus products do not detect it. %Temp% is a variable. The worm locates the Window temporary folder and copies its components to that location. For example, in Windows 2000, %Temp% can be C:\documents and settings\\local settings\temp. Installation A.exe is the worm's installer component. When it runs, it does the following: Copies itself to %System%\folder as these files: a.bat a.com a.exe a.pif a.scr a.sys Copies Explore.exe and SMTP.ocx to the %System%folder. Adds the value: "Explore"="%System%\explore.exe" to the registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run so that the worm's component runs when you restart Windows. Spread routine Explore.exe is the worm's component that contains its spread routine. When it runs, it does the following: Adds the value "a" to the registry key: HKEY_LOCAL_MACHINE\Software\Microsoft\Windows The worm uses this key as its infection marker. Changes the home page of Internet Explorer to www.geocities.com/yori_mrakkadi." Adds a value "DeathTime" to the registry key: HKEY_CURRENT_USER The value increases by 1 each time Explore.exe runs. When the value reaches 30, the worm disables the mouse and keyboard. Locates the KaZaA download folder through the registry. Searches for files whose extensions are .doc, .jpg, .mdb, .pps, .ram, .xls, or .zip. Then, it copies the worm to the KaZaA download folder using the file names. Retrieves the current users email address and default SMTP server IP address. Retrieves the email addresses from the files whose extensions are .htm, .html, .eml, and .txt. Retrieves the email addresses from the Outlook address book and MSN messenger contact list. Uses SMTP.ocx to send the worm to the email addresses it finds. The worm uses the filename it runs from as the attachment name. The subject line is one of the following: Fw: Re: You gonna love it Here is what u wanted Check this out ;) Enjoy! This is all i can send Have Fun :) Wait for more :) looool Take a look Never mind ! See the attatched file gift :) Surprise! save it for hard times Happy Times :) Useful Very funny Try it you have to see this! emazing! Steals network information and emails it to a predefined email address. The stolen information may include: Host name for the computer Domain in which the computer is registered Set of DNS servers IP address, which the computer uses DHCP server IP address, which the computer uses 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. 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. The following instructions pertain to all current and recent Symantec antivirus products, including the Symantec AntiVirus and Norton AntiVirus product lines. Disable System Restore (Windows Me/XP). Update the virus definitions. Restart the computer in Safe Mode or VGA mode. Run a full system scan and delete all the files detected as W32.Galil.C@mm. Delete the value that was added 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: "How to disable or enable Windows Me System Restore" "How to turn off or turn on Windows XP System Restore" 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. Restarting the computer in Safe mode or VGA mode Shut down the computer and turn off the power. Wait for at least 30 seconds, and then restart the computer in Safe mode or VGA mode. For Windows 95, 98, Me, 2000, or XP users, restart the computer in Safe mode. For instructions, read the document, "How to start the computer in Safe Mode." For Windows NT 4 users, restart the computer in VGA mode. 4. Scanning for and deleting the infected files Start your Symantec antivirus program and make sure that it is configured to scan all the files. For Norton AntiVirus consumer products: Read the document, "How to configure Norton AntiVirus to scan all files." For Symantec AntiVirus Enterprise products: Read the document, "How to verify that a Symantec Corporate antivirus product is set to scan all files." Run a full system scan. If any files are detected as infected with W32.Galil.C@mm, click Delete. 5. Deleting the value from the registry WARNING: 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. Click Start, and then click Run. (The Run dialog box appears.) Type regedit Then click OK. (The Registry Editor opens.) Navigate to the key: HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main In the right pane, modify the value "Start Page". Navigate to the key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows In the right pane, delete the value "a." Navigate to the key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows In the right pane, delete the value "a." Navigate to the key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run In the right pane, delete the value: "Explore"="%System%\explore.exe" Exit the Registry Editor. Write-up by: Yana Liu