A program or set of programs which hides itself by subverting or evading the computer's security mechanisms, then allows remote users to secretly control the computer's operating system.
Depending on the settings of your F-Secure security product, it will either automatically delete, quarantine or rename the suspect file, or ask you for a desired action.
More scanning & removal options
More information on the scanning and removal options available in your F-Secure product can be found in the Help Center.
You may also refer to the Knowledge Base on the F-Secure Community site for more information.
Rootkit:W32/Kobchka is a Generic Detection that identifies files with rootkit-like characteristics or behavior.