Hi,
After reviewing the forti demos at https://www.fortinet.com/demo-center and the documentation and some trainings I wondered what layer 3/4 and expecially layer 7 HTTP auto DOS protections are available without configuring manual thresholds in FortiDDos, FortiWeb, FortiADC ?
I mean like by triggering DOS protection based on the web server latency in HTTP responses or web server starting to return more 5xx response codes ?
I beliave that only fortiDOS offers auto thresholds as in the HTTP profile I see no manual thresholds like in FortiWeb or FortiADC but if I could get a confirmation?
Hello @filiaks1,
I believe a Custom Policy in FortiWeb would be some sort of threshold control for such scenario.
1. Match range 5XX return codes
2. Define occurrences in specific time period
Thanks.
Regards,
Shafiq
Not a bad idea @shafiq23 and the custom policy can track more than just IP address like user and session. Still it is not dynamic as I would have hoped but it is there. Probably TCL script can do the same but custom policy seems more readable as scripting I saw is also in FortiADC but not the custom policy.
Outside of that I saw that fortiddos is uses auto behavioral thresholds that are based on the number of http packets that are expected in a particular time window not the server latency/response codes.
Extra note during DDOS the servers can stop replying or send 503 like Nginx and after playing with the Custom Policy unfortunatly this is more to block attackers that trigger 5xx errors @shafiq23 not for triggering DOS protections?
Maybe if everyone could start getting javascript or captcha checks if many 5xx errors are seen with a custome policy or TCL script config not just the user generating the current traffic as they could be not attackers even if they get 5xx because of the server utlization?
Also what you showed with the custom policy and response codes I think the FortiWeb ML can do this automatically FortiWeb Bot Protection: Machine Learning based Protection
An extra question @shafiq23 is FortiWeb Bot needing javascripts as if the traffic is API? I think only biometric and deception need a javascript?
Hello @filiaks1,
ML based bot detection is also a good approach to detect deviation of HTTP error responses(return codes larger than 400).
Previous sample custom policy is used to statically block occurrences of HTTP 5XX responses - it might block legitimate requests.
From my understanding, js is inserted when Bot Confirmation is enabled and if the response is is HTML.
Thanks.
Regards,
Shafiq
Created on 06-23-2025 12:24 AM Edited on 06-23-2025 12:26 AM
This will not be anabled for API traffic that much I am aware of as this checks if you are a browser and we don't want that. Also the response will not be html for API but thanks for confirming this detection by FortiWeb.
Configuring bot detection policy | FortiWeb 7.0.1 | Fortinet Document Library
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