Antivirus scanning using flow-based inspection


In this recipe, you will turn on flow-based inspection on your FortiGate and apply flow-based antivirus scanning to network traffic.

For more information about the different antivirus inspection modes available in FortiOS, see FortiOS antivirus inspection modes.

Find this recipe for other FortiOS versions
5.4 | 6.0

1. Verifying the inspection mode

Flow-based is the default inspection mode for FortiOS. To verify that your FortiGate is in this mode, go to System > Settings and locate System Operations Settings.


Verify that Inspection Mode is set to Flow-based and NGFW Mode is set to Profile-based.

2. Configuring the AntiVirus profile

Go to System > Feature Visibility and verify that AntiVirus is enabled under Security Features.


To edit the default antivirus profile, go to Security Profiles > AntiVirus.

Set Scan Mode to Full and Detect Viruses to Block.


Under APT Protection Options, enable Use Virus Outbreak Prevention Database to provide an additional layer of protection from early stage virus outbreaks.

3. Enabling antivirus in a policy

To edit your Internet access policy, go to Policy & Objects > IPv4 Policy.

Under Security Profiles, enable AntiVirus and select the default profile.

SSL Inspection is enabled by default. Select deep-inspection.


4. Results

To test the antivirus scanning, go to and attempt to download a test file. The browser will display a message denying permission to download the file.
To view information about the blocked file, go to FortiView > Traffic from LAN/DMZ > Threats.

For further reading, check out Antivirus in the FortiOS 6.0 Online Help.

Victoria Martin

Technical Writer at Fortinet
Victoria Martin works in Ottawa as part of the FortiOS technical documentation team. She graduated with a Bachelor's degree from Mount Allison University, after which she attended Humber College's book publishing program, followed by the more practical technical writing program at Algonquin College. She does need glasses but also likes wearing them, since glasses make you look smarter.
Victoria Martin

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Using the deep-inspection profile may cause certificate errors. See Preventing certificate warnings for more information.