CSC ("CorelScript") is a prefix indentifying Corel Script viruses. These viruses replicate within Corel Script files ("*.csc").
Corel Script is a script language that is included within several Corel's applications, including Corel Draw.
For more information, please look at the description of the first Corel Script virus, CSV.
Once detected, the F-Secure security product will automatically disinfect the suspect file by either deleting it or renaming it.