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ctrlpan.dll

what is it?
ctrlpan.dll is associated with a trojan horse virus called Trojan.Bookmarker.B

What does it do?
This Trojan changes the Internet Explorer home page to webcoolsearch.com. It is also packed with UPX. It is a variant of trojan.bookmarker that modifies the Internet Explorer home page and search page and adds bookmarks, which point to pornographic Web sites; into the Favorites folder!.

When the Ctrlpan.dll file is loaded, it does the following:
  1. Creates the file hh.htt
  2. Adds the value:

    "AppInit_DLLs"="ctrlpan.dll"

    to the registry key:

    HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindows NTCurrentVersionWindows

    so that each Windows-based program running......................
More info and Removal instructions
@symantec