Hacktool.PWS.QQPass

SUMMARY

Hacktool.PWS.QQPass is a Trojan creation tool. The Trojans created with this tool can be programmed to steal dial-up networking telephone numbers and passwords, as well as the passwords of OICQ, which is a popular Chinese chat program. The filename of the file detected as Hacktool.PWS.QQPass consists of five random letters with the .exe extension.

Then, the Trojan sends this information to a specified set of email addresses.

Protection

• Virus Definitions (LiveUpdate™ Weekly) March 19, 2003
• Virus Definitions (Intelligent Updater) March 13, 2003

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
• Releases Confidential Info: Attempts to send dial-up networking credentials and OICQ passwords to a specifed set of email addresses

Distribution

• Distribution Level: Low

TECHNICAL DETAILS

Hacktool.PWS.QQPass can be used to create the server part of a backdoor Trojan. The Trojan that it creates is approximately 46 K in length and is compressed using ASPack. The created Trojan runs on Windows 95/98/Me systems only, and it may be detected as Backdoor.Trojan.

When the Trojan that Hacktool.PWS.QQPass created is run, it does the following:

1. Copies itself to the Windows installation folder and Windows system folder, using randomly generated filenames. The filename has five random letters as the name and .exe as the extension.
   
2. Adds the value:
   
   msgserv_ %System%<the Trojan file>
   
   to the registry key:
   
   HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersionRun
   
   so that the Trojan runs when you start Windows.
   
3. Adds the values:
   
   system_ %System%<the Trojan file>
   userfile_ %System%<*.dll>
   windows32_ <the Trojan file>
   
   to the registry key:
   
   HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersion
   
   For example, if the Trojan file is Moqsu.exe.exe, the .dll filename will be Moqsu.dll. The Trojan uses this .dll file to store the stolen information.
   
4. Inserts the following line in the [boot] section of the System.ini file:
   
   shell=explorer.exe %System%<the Trojan file>
   
   so that the Trojan runs when you start Windows.
   
5. Registers its process as a service. Because it uses the RegisterServiceProcess API, the Trojan can only run under Windows 98. The Hacktool itself can run on all Windows-based operating systems.
   
6. Steals information from your computer and sends the information to a predefined email address. The stolen information includes:
   • Dial-up networking telephone numbers
   • User name and passwords
   • OICQ UID number and password

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

The following instructions pertain to 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 the files detected as Hacktool.PWS.QQPass or Backdoor.Trojan.
3. Delete the value that was added to the registry.
4. Remove the text that was added to the System.ini file.

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

1. 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 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. 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.
   • 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."
2. Run a full system scan.
3. If any files are detected as infected with Hacktool.PWS.QQPass or Backdoor.Trojan, click Delete.

3. Deleting the value from the registry

CAUTION: Symantec strongly recommends that you back up the registry before you make 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_MACHINESOFTWAREMicrosoftWindowsCurrentVersionRun
   
4. In the right pane, delete the value:
   
   msgserv_ %System%<the Trojan file>
   
5. Exit the Registry Editor.

4. Removing the text from the System.ini file

1. The function you perform depends on your operating system:
   • Windows 95/98: Go to step b.
   • Windows Me: If you are running Windows Me, the Windows Me file-protection process may have made a backup copy of the System.ini file that you need to edit. If this backup copy exists, it will be in the C:WindowsRecent 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:WindowsRecent folder.
     3. In the right pane, select the System.ini file and delete it. The System.ini file will be regenerated when you save your changes to it in step f.
        
2. Click Start, and then click Run.
3. Type the following:
   
   edit c:windowssystem.ini
   
   and then click OK. (The MS-DOS Editor opens.)
   
   NOTE: If Windows is installed in a different location, make the appropriate path substitution.
   
4. In the [boot] section of the file, look for a line similar to:
   
   shell = Explorer.exe %System%<the Trojan file>
   
5. If this line exists, delete everything to the right of Explorer.exe.
   
   When you are done, it should look like:
   
   shell = Explorer.exe
   
6. Click File, and then click Save.
7. Click File, and then click Exit.