We've upgraded to FortiOS 6 on 4/27. We are seeing a strange bug where random sites will be blocked. The FortiGate will present a FortiGuard web filter block screen with no category. I found the following message in the web filter logs for each of the blocked sites. I haven't configured any URL filter lists; especially ones that include blocking of our major customers' sites.
I did find that refreshing the screen would load the site. I'm assuming this is a bug. I've submitted a ticket to FortiNet and they are "researching" the problem.
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