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Adware.BlockChecker

Adware.BlockChecker

Updated:
February 13, 2007
Publisher:
block-checker.com
Risk Impact:
Medium
File Names:
block-checker.exe
Systems Affected:
Windows

Behavior


Adware.BlockChecker is an adware program that sends its advertisements to contacts of instant messenger.

Symptoms


Unexpected advertisements are sent to contacts of instant messenger.

Behavior


This security risk is manually installed as a component of Block Checker.

Antivirus Protection Dates

  • Initial Rapid Release version October 02, 2014 revision 022
  • Latest Rapid Release version February 01, 2015 revision 020
  • Initial Daily Certified version August 25, 2005
  • Latest Daily Certified version May 01, 2011 revision 002
  • Initial Weekly Certified release date August 31, 2005
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

When Adware.BlockChecker is executed, it performs the following actions:
  1. Adds the value:

    "BlockChecker" = "path of itself"

    to the registry subkey:

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run

    so that the risk runs every time Windows starts.

  2. Creates the following registry subkeys:

    HKEY_CURRENT_USER\Software\VB and VBA Program Settings\IMAdvertiser\MSN
    HKEY_CURRENT_USER\Software\VB and VBA Program Settings\IMAdvertiser\Yahoo
    HKEY_CURRENT_USER\Software\VB and VBA Program Settings\IMAdvertiser\AOL

  3. Sends one of the following messages to the contacts of Microsoft Messenger, Yahoo Instant Messenger and AOL Instant Messenger:

    • Find out who's blocking you on MSN, Download it free from [http://]www.block-checker[REMOVED].com
    • Did you know you can find out who blocked you on MSN? Check it out, it's free [http://]www.block-checker[REMOVED].com
    • I know who's blocking me on MSN because I use [http://]www.block-checker[REMOVED].com
    • Did they block you too? Download a free MSN Block Checker [http://]www.block-checker[REMOVED].com
    • Hey you can see who's blocking you on MSN! Download it now [http://]www.block-checker[REMOVED].com
    • Find out who's blocking you on Yahoo, Download it free from [http://]www.block-checker[REMOVED].com
    • Did you know you can find out who blocked you on Yahoo? Check it out, it's free [http://]www.block-checker[REMOVED].com
    • I know who's blocking me on Yahoo because I use [http://]www.block-checker[REMOVED].com
    • Did they block you too? Download a free Yahoo Block Checker [http://]www.block-checker[REMOVED].com
    • I know who's blocking me on AIM because I use [http://]www.block-checker[REMOVED].com
    • Find out who's blocking you on AIM, Download it free from [http://]www.block-checker[REMOVED].com
    • Did you know you can find out who blocked you on AIM? Check it out, it's free [http://]www.block-checker[REMOVED].com
    • Did they block you too? Download a free AIM Block Checker [http://]www.block-checker[REMOVED].com
    • Hey you can see who's blocking you on AIM! Download it now [http://]www.block-checker[REMOVED].com



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
To obtain the most recent definitions, start your Symantec program and run LiveUpdate.


2. To run the scan
  1. Start your Symantec antivirus program, and then run a full system scan.
  2. If any files are detected, 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 risk 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 risk 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 risk for this scan only, and thus, the risk 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.

    • 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 risk 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.

Important: If you are unable to start your Symantec antivirus product or the product reports that it cannot delete a detected file, you may need to stop the risk from running in order to remove it. To do this, run the scan in Safe mode. For instructions, read the document, How to start the computer in Safe Mode . Once you have restarted in Safe mode, run the scan again.

After the files are deleted, restart the computer in Normal mode and proceed with the next section.

Warning messages may be displayed when the computer is restarted, since the risk may not be fully removed at this point. You can ignore these messages and click OK. These messages will not appear when the computer is restarted after the removal instructions have been fully completed. The messages displayed may be similar to the following:

Title: [FILE PATH]
Message body: Windows cannot find [FILE NAME]. Make sure you typed the name correctly, and then try again. To search for a file, click the Start button, and then click Search.

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.

    Note: If the registry editor fails to open the risk may have modified the registry to prevent access to the registry editor. Security Response has developed a tool to resolve this problem. Download and run this tool, and then continue with the removal.

  3. Navigate to the subkey:

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run

  4. In the right pane, delete the value:

    "BlockChecker" = "path of the Adware"

  5. Navigate and deletes the following keys:

    HKEY_CURRENT_USER\Software\VB and VBA Program Settings\IMAdvertiser\MSN
    HKEY_CURRENT_USER\Software\VB and VBA Program Settings\IMAdvertiser\Yahoo
    HKEY_CURRENT_USER\Software\VB and VBA Program Settings\IMAdvertiser\AOL

  6. Exit the Registry Editor.