Antivirus is used as a catch all term to describe the technology for protection against the transmission of malicious computer code sometimes referred to as malware. As anyone who has listened to the media has heard that the Internet can be a dangerous place filled with malware of various flavours. Currently, the malware that is most common in the Internet, in descending order, is Trojan horses, viruses, worms, adware, back door exploits, spyware and other variations. In recent years, not only has the volume of malicious software become greater than would have been believed when it first appeared but the level of sophistication has risen as well.

The Antivirus Filter works by inspecting the traffic that is about to be transmitted through the FortiGate. To increase the efficiency of effort it only inspects the traffic being transmitted via the protocols that it has been configured to check. Before the data moves across the FortiGate firewall from one interface to another it is checked for attributes or signatures that have been known to be associated with malware. If malware is detected, it is removed.