METHOD FOR PROTECTING COMPUTER SYSTEMS AGAINST ENCRYPTED AND POLYMORPHOUS VIRUSES

摘要

The invention relates to computer engineering, information systems and to means for protection against non-authorised access. Said invention makes it possible to increase the efficiency of computer system protection against encrypted and polymorphous viruses. The inventive method consists in encoding the executable file of each program introduced into the computer system by means of different keys for separately encoding the sequence of command codes and a data set. The effect of an encrypted or polymorphous virus on an open source code and program data is excluded by means of the command-by-command decoding of the program during the execution thereof. The effect of the encrypted or polymorphous virus on encrypted command codes or encrypted data is disclosed by detecting distortions therein, the distorted commands are determined as a virus body and the execution of the program containing said virus body is blocked in order to prevent the infection of other programs.