Messaging virus protection program and the like

A messaging virus protection program which causes a computer to deal with messaging viruses that are transmitted along with electronic information that is distributed between a specified network and another network, characterized in that said computer is caused to execute the steps of:

• determining, when electronic information with said messaging virus is received, whether or not the messaging virus attached to said received electronic information is a transmission source falsifying virus that misrepresents the transmission source of the electronic information with the messaging virus, this being determined on the basis of predetermined characteristics of the messaging virus;
• transmitting a virus detection notification message giving notification that a virus has been detected to the transmission source of said received electronic information in cases where it is determined that said received messaging virus is not a transmission source falsifying virus, and determining whether or not said received electronic information has been transmitted from said specified network in cases where it is determined that said received messaging virus is a transmission source falsifying virus;
• and
• transmitting said virus detection notification message in cases where it is determined that said received electronic information has been transmitted from said specified network, but not transmitting said virus detection notification message in cases where it is determined that said received electronic information has not been transmitted from said specified network.

A messaging virus protection program which causes a computer to deal with messaging viruses that are transmitted along with electronic information that is distributed between a specified network and another network, characterized in that said computer is caused to execute the steps of:

• determining, when electronic information with said messaging virus is received, whether or not the messaging virus attached to said received electronic information is an unspecified file attachment type virus that attaches and transmits an arbitrary file in a computer, this being determined on the basis of predetermined characteristics of the messaging virus;
• transmitting said received electronic information to the transmission destination in cases where it is determined that said received messaging virus is not an unspecified file attachment type virus, and determining whether or not said received electronic information has been transmitted from said specified network in cases where it is determined that said receive messaging virus is an unspecified file attachment type virus;
• and
• transmitting said received electronic information in cases where it is determined that said received electronic information has not been transmitted from said specified network, but not transmitting said received electronic information in cases where it is determined that said received electronic information has been transmitted from said specified network.

A messaging virus protection system which deals with messaging viruses that are transmitted along with the delivery of electronic information on a network, said system comprising:

• a storage unit which stores information of the characteristics of known messaging viruses whose characteristics have been determined beforehand;
• and
• a virus processing unit which judges whether or not processing is to be performed in the warning mode on the basis of information which is input into said messaging virus protection system, and which warns or does not warn of a new type of messaging virus whose characteristics have not been determined beforehand,
• in cases where it is judged that processing is to be performed in said warning mode, determines on the basis of specified conditions whether or not there is any danger of viral infection by said received electronic information, and in cases where it is determined that there is a danger of said viral infection, stores said received electronic information without being delivered, while in cases where it is determined that there is no danger of said viral infection, delivers said received electronic information, and
• in cases where it is judged that processing is not to be performed in said warning mode, performs processing for said received electronic information on the basis of the characteristics of known messaging viruses stored in said storage unit.

A messaging virus protection system which deals with messaging viruses that are transmitted along with the delivery of electronic information on a network, said system comprising:

• a storage unit which stores information of the characteristics of known messaging viruses whose characteristics have been determined beforehand;
• and
• a virus processing unit which determines, when electronic information with said messaging virus is received, whether or not the messaging virus attached to said received electronic information is a transmission source falsifying virus that misrepresents the transmission source of the electronic information with the messaging virus, this being determined on the basis of characteristics of the messaging viruses stored in said storage unit, and
• in cases where it is determined that said received messaging virus is not a transmission source falsifying virus, transmits a virus detection notification message which gives notification that a virus has been detected to the transmission source of said received electronic information, while in cases where it is determined that said received messaging virus is a transmission source falsifying virus, does not transmit said virus detection notification message.

A messaging virus protection system which deals with messaging viruses that are transmitted along with the delivery of electronic information on a network, said system comprising:

• a storage unit which stores information of the characteristics of known messaging viruses whose characteristics have been determined beforehand;
• and
• a virus processing unit which determines, when electronic information with said messaging virus is received, whether or not the messaging virus attached to said received electronic information is an unspecified file attachment type virus which attaches and transmits an arbitrary file in a computer, this being determined on the basis of characteristics of the messaging viruses stored in said storage unit, and
• in cases where it is determined that said received messaging virus is not an unspecified file attachment type virus, transmits said received electronic information to the transmission destination, while in cases where it is determined that said received messaging virus is an unspecified file attachment type virus, does not transmit said received electronic information.

A messaging virus protection method in a computer system which deals with messaging viruses that are transmitted along with the delivery of electronic information on a network, the method comprising:

• a step where said computer system judges whether or not processing is to be performed in a warning mode on the basis of information either warning or not warning of a new type of messaging virus whose characteristics have not yet been determined, which is input into said computer;
• a step where said computer system determines whether or not there is a danger of viral infection by said received electronic information on the basis of specified conditions in cases where it is judged that processing is to be performed in said warning mode, stores said received electronic information without delivering said information in cases where it is determined that there is a danger of said viral infection, and delivers said received electronic information in cases where it is determined that there is no danger of said viral infection;
• and
• a step where said computer system performs processing for said received electronic information on the basis of said characteristics of known messaging viruses whose characteristics have been determined beforehand in cases where it is judged that processing is not to be performed in said warning mode.