Threat Explorer

The Threat Explorer is a comprehensive resource consumers can turn to for daily, accurate, up-to-date information on the latest threats, risks and vulnerabilities.

Adware.Riversoft

Adware.Riversoft

Updated:
February 13, 2007
Risk Impact:
Low
File Names:
x0ff.cab,x0ff.dll,x0ff0n.exe,x2ff.dll,x2ff.inf,csa.dll
Systems Affected:
Windows

Behavior


Adware.Riversoft is an adware program that uses a Web browser to display advertisements on the computer.

Symptoms


Your Symantec program detects this threat as Adware.Riversoft.

Behavior


This adware program must be manually installed. However, some programs may install it as part of their installation routine.

Antivirus Protection Dates

  • Initial Rapid Release version October 02, 2014 revision 022
  • Latest Rapid Release version March 04, 2015 revision 038
  • Initial Daily Certified version December 21, 2004
  • Latest Daily Certified version March 05, 2015 revision 003
  • Initial Weekly Certified release date December 21, 2004
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

When Adware.Riversoft runs, it does the following:
  1. Creates the following registry keys:

    HKEY_CLASSES_ROOT\AppID\csa.DLL
    HKEY_CLASSES_ROOT\AppID\x0ff.DLL
    HKEY_CLASSES_ROOT\AppID\x2ff.DLL
    HKEY_CLASSES_ROOT\AppID\{CCB76C32-C755-4859-B195-73DB23D55AC4}
    HKEY_CLASSES_ROOT\AppID\{D137514C-FFFA-492A-933B-D29145B7A468}
    HKEY_CLASSES_ROOT\AppID\{D1BB73A7-5D35-48C9-94C0-D0BD624B0F5D}
    HKEY_CLASSES_ROOT\CLSID\{ABD45F35-2E4C-44C0-A075-6EF1DE75398E}
    HKEY_CLASSES_ROOT\CLSID\{AC109D01-32D6-4EB5-8300-D3C5EBAC7C83}
    HKEY_CLASSES_ROOT\CLSID\{D319662B-D5BF-4538-ADF3-8D3E36362608}
    HKEY_CLASSES_ROOT\TypeLib\{1D1A0231-322A-4024-A282-697bF547970E}
    HKEY_CLASSES_ROOT\TypeLib\{F81F7F91-8BA8-47DD-80FE-A262A4C8A985}
    HKEY_CLASSES_ROOT\TypeLib\{FEC81DDE-1320-4027-8D1D-72753D27B4F3}
    HKEY_CLASSES_ROOT\Interface\{248D0792-644C-403B-8525-AA2877603204}
    HKEY_CLASSES_ROOT\Interface\{B0C5E55E-53DF-4966-90A0-912D34CB64A7}
    HKEY_CLASSES_ROOT\Interface\{F1EA6966-79FB-47FA-AB97-8ED1A8D89DE4}
    HKEY_CLASSES_ROOT\AppID\x0ff.DLL
    HKEY_CLASSES_ROOT\x0ff.Xbrowse
    HKEY_CLASSES_ROOT\x0ff.Xbrowse.1
    HKEY_CLASSES_ROOT\x2ff.Xbrowse
    HKEY_CLASSES_ROOT\x2ff.Xbrowse.1
    HKEY_CLASSES_ROOT\csa.accel
    HKEY_CLASSES_ROOT\csa.accel.1
    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Browser Helper Objects\{AC109D01-32D6-4EB5-8300-D3C5EBAC7C83}
    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Browser Helper {D319662B-D5BF-4538-ADF3-8D3E36362608}

    so that Adware.Riversoft starts as a browser helper object

  2. May create the following files:
    • %Documents and Settings%\All Users\Application Data\XOff\XOff.dll
    • %Documents and Settings%\All Users\Application Data\XOff\XOff.cfg
    • %Documents and Settings%\All Users\Application Data\XOff\X2ff.cfg

      Note: %UserProfile% is a variable that refers to the current user's profile folder. By default, this is C:\Documents and Settings\<Current User> (Windows NT/2000/XP).

  3. Contacts the domain www.riversoftware.net to download advertisements and register statistical data.

  4. Displays advertisements depending on Web sites visited.



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 the value that was 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 as Adware.Riversoft 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.

    • 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.


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 keys only. Read the document, "How to make a backup of the Windows registry ," for instructions.

  1. Click Start > Run.
  2. Type regedit

    Then click OK.

  3. Navigate to and delete the keys:
      HKEY_CLASSES_ROOT\AppID\csa.DLL
      HKEY_CLASSES_ROOT\AppID\x0ff.DLL
      HKEY_CLASSES_ROOT\AppID\x2ff.DLL
      HKEY_CLASSES_ROOT\AppID\{CCB76C32-C755-4859-B195-73DB23D55AC4}
      HKEY_CLASSES_ROOT\AppID\{D137514C-FFFA-492A-933B-D29145B7A468}
      HKEY_CLASSES_ROOT\AppID\{D1BB73A7-5D35-48C9-94C0-D0BD624B0F5D}
      HKEY_CLASSES_ROOT\CLSID\{ABD45F35-2E4C-44C0-A075-6EF1DE75398E}
      HKEY_CLASSES_ROOT\CLSID\{AC109D01-32D6-4EB5-8300-D3C5EBAC7C83}
      HKEY_CLASSES_ROOT\CLSID\{D319662B-D5BF-4538-ADF3-8D3E36362608}
      HKEY_CLASSES_ROOT\TypeLib\{1D1A0231-322A-4024-A282-697bF547970E}
      HKEY_CLASSES_ROOT\TypeLib\{F81F7F91-8BA8-47DD-80FE-A262A4C8A985}
      HKEY_CLASSES_ROOT\TypeLib\{FEC81DDE-1320-4027-8D1D-72753D27B4F3}
      HKEY_CLASSES_ROOT\Interface\{248D0792-644C-403B-8525-AA2877603204}
      HKEY_CLASSES_ROOT\Interface\{B0C5E55E-53DF-4966-90A0-912D34CB64A7}
      HKEY_CLASSES_ROOT\Interface\{F1EA6966-79FB-47FA-AB97-8ED1A8D89DE4}
      HKEY_CLASSES_ROOT\AppID\x0ff.DLL
      HKEY_CLASSES_ROOT\x0ff.Xbrowse
      HKEY_CLASSES_ROOT\x0ff.Xbrowse.1
      HKEY_CLASSES_ROOT\x2ff.Xbrowse
      HKEY_CLASSES_ROOT\x2ff.Xbrowse.1
      HKEY_CLASSES_ROOT\csa.accel
      HKEY_CLASSES_ROOT\csa.accel.1
      HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Browser Helper Objects\{AC109D01-32D6-4EB5-8300-D3C5EBAC7C83}
      HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Browser Helper {D319662B-D5BF-4538-ADF3-8D3E36362608}

  4. Exit the Registry Editor.