Once executed the trojan copies itself to the following location:
It drops the following two files, a desktop wallpaper and a screensaver:
The ctfmonb.bmp file is set as the desktop wallpaper to warn the user of a non-existent spyware infection.
The file called blackster.scr is set as the system's screensaver. Once it activates, a legion of bugs appear to eat away the desktop. The screensaver appears to not have been made by authors of the trojan. The original version is available on the Internet as freeware.Therefore having a similar screensaver alone does not mean you have a trojan on your computer.
To enable its execution on start-up and to change the wallpaper and screensaver, the trojan makes several changes to the system registry. Trojan:W32/Pakes.CSG also disables System Restore with a registry modification.The following is a list of the registry changes made by Pakes.CSG:
- HKLM\Software\Microsoft\Software Notifier InstallationID = 30ca1f71-3146-4d7b-a35f-3736e1cd05bd
- HKCU\Control Panel\Colors Background = 0 0 255
- HKCU\Control Panel\Desktop WallpaperStyle = 0 [Wallpaper Changed]
- HKCU\Control Panel\Desktop TileWallpaper = 0
- HKCU\Control Panel\Desktop Wallpaper = C:\WINDOWS\system32\ctfmonb.bmp [Wallpaper Changed]
- HKCU\Control Panel\Desktop OriginalWallpaper = C:\WINDOWS\system32\ctfmonb.bmp
- HKCU\Control Panel\Desktop ConvertedWallpaper = C:\WINDOWS\system32\ctfmonb.bmp
- HKLM\Software\Microsoft\Windows\CurrentVersion\Run ctfmona = C:\WINDOWS\system32\ctfmona.exe [Launchpoint: Run]
- HKLM\System\CurrentControlSet\Services\srservice Start = 00000002
- HKLM\System\CurrentControlSet\Services\sr Start = 00000000
- HKLM\System\CurrentControlSet\Services\sr ImagePath = system32\DRIVERS\sr.sys [Launchpoint: Service]
- HKLM\Software\Microsoft\Windows NT\CurrentVersion\SystemRestore DisableSR = 00000000 [System Restore Disabled]
- HKCU\Control Panel\Desktop SCRNSAVE.EXE = C:\WINDOWS\system32\blackster.scr
Once running the trojan posts information to the following location:
The information sent by the trojan includes hardware and Operating System information, installed software, and currently running processes.The trojan also attempts to connect to the following location:
Connecting to Windows Update tests if the computer has a working Internet connection. The trojan then attempts to download a file from:
The goal of this trojan is to install and push the sale of a rogue application. Rogue applications produce fraudulent scan results and use affiliate programs to market themselves. Trojans such as Pakes.CSG are designed and used by unscrupulous affiliates.More details are available from the Rogue antispyware description.