IUAM for specific IPs

Does Cloudflare offer I am under attack for specific IPs? I have an unknown adversary that’s being a pest over the last few days. Cloudflare firewall is blocking the fool but it the traffic is drowning my analytics. I found that IUA is effective against the offender but they keep changing the path.
Does Cloudflare offer IUAM for specfic IPs? I have three IPs (,, and that I would like to deal with.
This is a search for information as the firewall is successfully blocking the ‘attack.’
Thank you.

Try firewall rules. Create one that matches those IPs and set the action to ‘JS challenge” which is the same thing as IUAM.

Done. Thanks.
I’m curious is this different from creating JS Challenge under Tools?
We have implemented ‘Block’ rules of these IPs under Firewall tools option, and it is blocking the fool so I am hoping that JS Challenge or IUAM will slow them down.
Thank you.

Are all the different ways to enable JS challenge equivalent?
As you know, there are many ways to enable JS Challenge. I am currently using the option in Firewall->Tool->IP address->JS Challenge
However, I have access to Firewall->Rules->Create Firewall Rules with an option to match on IP address (list), → JS Challenge.

Are these two methods equivalent, or is one any stronger?

Ideally, I would like to nominate these IP addresses to some authority and have them kicked offline.

JS Challenge is the same mechanism no matter how it’s triggered.

Sounds like a job for the newly formed Protocol Police :grinning:

Personally, I’d look at the organisation that owns the offending IP ranges, realise I don’t have any users inside a Polish/Estonian hosting platform, and just block both ranges. You could also email the abuse contact for those ranges, but might not be worth the trouble.


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