System and method for antivirus checking of files based on level of trust of their digital certificates

Disclosed are a method, a system and a computer program product for performing antivirus checking of files based on a level of trust of their digital certificates. An example method includes obtaining a digital certificate of a digital signature of a file; determining a validity of the obtained digital certificate; assigning a level of trust to the digital certificate based on the determined validity or invalidity of the digital certificate of the file; based on the assigned level of trust of the digital certificate of the file, determining what antivirus checking method to perform on the file; and performing the determined antivirus checking method on the file.