Adware.AdBlock

SUMMARY

Behavior

When Adware.AdBlock is installed, it adds a toolbar button to the Internet Explorer and redirects to unwanted advertizement web pages.

Symptoms

One or more files are detected as Adware.AdBlock.

Transmission

The program can be installed while brousing websites or can be manually installed.

Protection

• Virus Definitions (LiveUpdate™ Weekly) April 6, 2005
• Virus Definitions (Intelligent Updater) April 6, 2005

TECHNICAL DETAILS

When Adware.AdBlock is installed, the following actions are performed:

1. Creates the following files:
   
   • %Windir%Downloaded Program FilesAPHelper.dll
     
     
     Note:
   • %Windir% is a variable that refers to the Windows installation folder. By default, this is C:Windows or C:Winnt.
     
     
2. Creates the following registry keys:
   
   • HKEY_LOCAL_MACHINESOFTWAREClassesCLSID{54EC170F-6EB1-47C6-9C4D-EB0BE20CE45E}
   • HKEY_LOCAL_MACHINESOFTWAREClassesCLSID{93829908-07C2-44A2-95DB-F78F201A9B48}
   • HKEY_LOCAL_MACHINESOFTWAREClassesCLSID{CCF99CD5-1BCF-4DB2-8197-E9864A99702B}
   • HKEY_LOCAL_MACHINESOFTWAREClassesInterface{12DEBC84-B743-423A-825C-049AD85309DC}
   • HKEY_LOCAL_MACHINESOFTWAREClassesInterface{9B33399E-89A6-4EA5-91A9-5DC72B7AF60A}
   • HKEY_LOCAL_MACHINESOFTWAREClassesInterface{EE1BC3C2-D245-4E64-A6B6-06425A3A5997}
   • HKEY_LOCAL_MACHINESOFTWAREClassesTypeLib{A37D57BD-5A27-4F8C-AB59-E0F6A7A0E95A}
   • HKEY_LOCAL_MACHINESOFTWAREClassesAPHelper.APConfig
   • HKEY_LOCAL_MACHINESOFTWAREClassesAPHelper.APConfig.1
   • HKEY_LOCAL_MACHINESOFTWAREClassesAPHelper.APInstaller
   • HKEY_LOCAL_MACHINESOFTWAREClassesAPHelper.APInstaller.1
   • HKEY_LOCAL_MACHINESOFTWAREClassesAPHelper.APToolBarHelper
   • HKEY_LOCAL_MACHINESOFTWAREClassesAPHelper.APToolBarHelper.1
   • HKEY_LOCAL_MACHINESOFTWAREMicrosoftInternet ExplorerExtensions{7E34CCAC-2531-450E-8746-80DA107ADAF5}
   • HKEY_LOCAL_MACHINESOFTWAREMicrosoftInternet ExplorerExtensions{D1E435DB-EE0C-4A71-84A8-A270F03B3EE7}
   • HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindowsCurrentVersionExplorerBrowser Helper Objects{54EC170F-6EB1-47C6-9C4D-EB0BE20CE45E}
   • HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindowsCurrentVersionUninstall{93829908-07C2-44A2-95DB-F78F201A9B48}
   • HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindowsCurrentVersionModuleUsageC:/WINDOWS/Downloaded Program Files/APHelper.dll
   • HKEY_LOCAL_MACHINESOFTWAREMicrosoftCode Store DatabaseDistribution Units{93829908-07C2-44A2-95DB-F78F201A9B48}
   • HKEY_CURRENT_USERSoftwareLinkz
     
     
3. Adds the value:
   
   "%Windir%Downloaded Program FilesAPHelper.dll" = "0x00000001"
   
   to the registry subkey:
   
   HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindowsCurrentVersionSharedDLLs
   
   
4. Adds the value:
   
   "Search Bar" = "http://adblock.linkz.com/abho/bandsearch.abs"
   
   to the registry subkey:
   
   HKEY_CURRENT_USERSoftwareMicrosoftInternet ExplorerMainSearch Bar
   
   
5. Modifies the value:
   
   "SearchAssistant" = "http://adblock.linkz.com/abho/bandsearch.abs"
   
   in the registry key:
   
   HKEY_LOCAL_MACHINESOFTWAREMicrosoftInternet ExplorerSearch
   
   
6. Modifies the value:
   
   "Search Page" = "http://linkz.com/"
   
   in the registry key:
   
   HKEY_LOCAL_MACHINESoftwareMicrosoftInternet ExplorerMain
   
   
7. Adds tool bar button to the Internet Explorer and claims to be a popup blocker.

REMOVAL

The following instructions pertain to all Symantec antivirus products that support security risk detection.

1. Update the definitions.
2. Run a full system scan.
3. Delete any values added to the registry.
   

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

1. To update the 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 document: Virus Definitions (LiveUpdate).
• Downloading the definitions using the Intelligent Updater: The Intelligent Updater virus definitions are posted daily. 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 document: Virus Definitions (Intelligent Updater).
  
  The latest Intelligent Updater virus definitions can be obtained here: Intelligent Updater virus definitions. For detailed instructions read the document: How to update virus definition files using the Intelligent Updater.

2. To run the scan

1. Start your Symantec antivirus program, and then run a full system scan.
   
2. If any files are detected as Adware.AdBlock and depending on which software version you are using, you may see one or more of the following options:
   
   Note: This applies only to versions of Norton AntiVirus that support security risk detection. If you are running a version of Symantec AntiVirus Corporate Edition that supports security risk detection, and security risk detection has been enabled, you will only see a message box that gives the results of the scan. If you have questions in this situation, contact your network administrator.
   
   • Exclude (Not recommended): If you click this button, it will set the threat so that it is no longer detectable. That is, the antivirus program will keep the security risk on your computer and will no longer detect it to remove from your computer.
     
     
   • Ignore or Skip: This option tells the scanner to ignore the threat for this scan only. It will be detected again the next time that you run a scan.
     
     
   • Cancel: This option is new to Norton Antivirus 2005. It is used when Norton Antivirus 2005 has determined that it cannot delete a security risk. This Cancel option tells the scanner to ignore the threat for this scan only, and thus, the threat will be detected again the next time that you run a scan.
     
     To actually delete the security risk:
     • Click its file name (under the Filename column).
     • In the Item Information box that displays, write down the full path and file name.
     • Then use Windows Explorer to locate and delete the file.
       
       If Windows reports that it cannot delete the file, this indicates that the file is in use. In this situation, complete the rest of the instructions on this page, restart the computer in Safe mode, and then delete the file using Windows Explorer. Restart the computer in Normal mode.
       
       
   • Delete: This option will attempt to delete the detected files. In some cases, the scanner will not be able to do this.
     • If you see a message, "Delete Failed" (or similar message), manually delete the file.
     • Click the file name of the threat that is under the Filename column.
     • In the Item Information box that displays, write down the full path and file name.
     • Then use Windows Explorer to locate and delete the file.
       
       If Windows reports that it cannot delete the file, this indicates that the file is in use. In this situation, complete the rest of the instructions on this page, restart the computer in Safe mode, and then delete the file using Windows Explorer. Restart the computer in Normal mode.

3. To delete the value from the registry
Important: 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 subkeys only. Read the document: How to make a backup of the Windows registry.

1. Click Start > Run.
   
   
2. Type regedit
   
   Then click OK.
   
   
3. Navigate to and delete the keys:
   
   • HKEY_LOCAL_MACHINESOFTWAREClassesCLSID{54EC170F-6EB1-47C6-9C4D-EB0BE20CE45E}
   • HKEY_LOCAL_MACHINESOFTWAREClassesCLSID{93829908-07C2-44A2-95DB-F78F201A9B48}
   • HKEY_LOCAL_MACHINESOFTWAREClassesCLSID{CCF99CD5-1BCF-4DB2-8197-E9864A99702B}
   • HKEY_LOCAL_MACHINESOFTWAREClassesInterface{12DEBC84-B743-423A-825C-049AD85309DC}
   • HKEY_LOCAL_MACHINESOFTWAREClassesInterface{9B33399E-89A6-4EA5-91A9-5DC72B7AF60A}
   • HKEY_LOCAL_MACHINESOFTWAREClassesInterface{EE1BC3C2-D245-4E64-A6B6-06425A3A5997}
   • HKEY_LOCAL_MACHINESOFTWAREClassesTypeLib{A37D57BD-5A27-4F8C-AB59-E0F6A7A0E95A}
   • HKEY_LOCAL_MACHINESOFTWAREClassesAPHelper.APConfig
   • HKEY_LOCAL_MACHINESOFTWAREClassesAPHelper.APConfig.1
   • HKEY_LOCAL_MACHINESOFTWAREClassesAPHelper.APInstaller
   • HKEY_LOCAL_MACHINESOFTWAREClassesAPHelper.APInstaller.1
   • HKEY_LOCAL_MACHINESOFTWAREClassesAPHelper.APToolBarHelper
   • HKEY_LOCAL_MACHINESOFTWAREClassesAPHelper.APToolBarHelper.1
   • HKEY_LOCAL_MACHINESOFTWAREMicrosoftInternet ExplorerExtensions{7E34CCAC-2531-450E-8746-80DA107ADAF5}
   • HKEY_LOCAL_MACHINESOFTWAREMicrosoftInternet ExplorerExtensions{D1E435DB-EE0C-4A71-84A8-A270F03B3EE7}
   • HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindowsCurrentVersionExplorerBrowser Helper Objects{54EC170F-6EB1-47C6-9C4D-EB0BE20CE45E}
   • HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindowsCurrentVersionUninstall{93829908-07C2-44A2-95DB-F78F201A9B48}
   • HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindowsCurrentVersionModuleUsageC:/WINDOWS/Downloaded Program Files/APHelper.dll
   • HKEY_LOCAL_MACHINESOFTWAREMicrosoftCode Store DatabaseDistribution Units{93829908-07C2-44A2-95DB-F78F201A9B48}
   • HKEY_CURRENT_USERSoftwareLinkz
     
     
4. Navigate to the subkey:
   
   HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindowsCurrentVersionSharedDLLs
   
   
5. In the right pane, delete the value:
   
   "C:WINDOWSDownloaded Program FilesAPHelper.dll" = "0x00000001"
   
   
6. Navigate to the subkey:
   
   HKEY_CURRENT_USERSoftwareMicrosoftInternet ExplorerMain
   
   
7. In the right pane, delete the value:
   
   "Search Bar" = "http://adblock.linkz.com/abho/bandsearch.abs"
   
   
8. Navigate to the subkey:
   
   HKEY_LOCAL_MACHINESOFTWAREMicrosoftInternet ExplorerSearch
   
   
9. In the right pane, modify the value:
   
   "SearchAssistant" = "<value>"
   
   
10. Navigate to the subkey:
    
    HKEY_LOCAL_MACHINESoftwareMicrosoftInternet ExplorerMain
    
    
11. In the right pane, modify the value:
    
    "Search Page" = "<value>"
    
    
12. Exit the Registry Editor.