FortiOS 6 – AntiVirus

Block files larger than 8 MB

Set proxy options profile to block files larger than 8 MB

  1. Go to Security Profiles > Proxy Options.
  2. Edit the default or select Create New to add a new one.
  3. Scroll down to the common Options Section and place a check in the box next to BlockOversized File/Email
  4. The sub line Threshold (MB) will appear with a value field. Enter 8.
  5. Select OK or Apply.

The proxy options profile is configured, but to block files, you must select it in the firewall policies handling the traffic that contains the files you want blocked.

To select the Proxy Options profile in a security policy

  1. Go to Policy & Objects > IPv4 Policy (or IPv6 Policy, depending).
  2. Edit or create a security policy.
  3. Select a proxy-based security profile. You will know that there is a proxy component to the Security Profile because when a Security Profile is Proxy based the Proxy Options field will be visible (for example, select an Antivirus profile that includes proxy scanning).
  4. Beside Proxy Options select the name of the MTU proxy options protocol.
  5. Select OK to save the security policy.
  6. Once you complete these steps, any files in the traffic subject to Security Profile scanning handled by this policy that are larger than 8MB will be blocked. If you have multiple firewall policies, examine each to determine if you want to apply similar file blocking the them as well.


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