How to when there is a "@" string in the path of the URL - 404 should be returned?

Example:

http://example.com/aa@aa.com/ - should return 404
http://example.com/img/ - should work as usual

Thanks in advance...

Use map;

map $request_uri $requri {
default 0;
~\@ 1;
}
...................
server {
if ($requri) { return 404; }
}

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