Hi,
Traffic being destined to the proxied IP on the SRX has nothing to do with the configuration.
You are getting that traffic as you are proxying for that IP (maybe hosting services) and any traffic originated from the Internet destined to your IP would reach the SRX Wan interface.
The traffic would be permitted only as per your security policies.
You can implement Screens :-
If there are specific IP addresses which are initiating that unwanted traffic, you can block them using filters on the interface :-
https://kb.juniper.net/InfoCenter/index?page=content&id=KB21872&smlogin=true&actp=search
(Use reject instead of accept)
HTH!
Regards,
Sahil Sharma
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