External links URL encoding leads to '%3F' and '%3D' on Nginx server

Question

I got a problem with my server. I got four inbound links to different sites of my dynamic webpage which look something like this:

myurl.com/default/Site%3Fid%3D13

They should look like this:

myurl.com/default/Site?id=13

I do know that those %3F is an escape sequence for the ? sign and the %3D is an escape sequence for the equal sign. But I do get an error 400 when I use those links. What can I do about that?

The four links are for different sites, and I imagine over time there will be more links like that. So one fix for all would be perfect.

Answer 1

An exact same question was actually asked on nginx-ru mailing list about a year ago:

http://mailman.nginx.org/pipermail/nginx-ru/2013-February/050200.html

The most helpful response, by an Nginx, Inc, employee/developer, Валентин Бартенев:

http://mailman.nginx.org/pipermail/nginx-ru/2013-February/050209.html

Если запрос приходит в таком виде, то это уже не параметры, а имя запрошенного файла. Другое дело, что location ищется по уже раскодированному адресу, о чем в документации написано.

Translation:

If the request comes in such a form, then these are no longer the args, but the name of the requested file. Another thing is that, as documented, the location matching is performed against a normalised URI.

His suggested solution, translated to the sample example from the question here at SO, would then be:

location /default/Site? {
    rewrite \?(.*)$ /default/Site?$1? last;
}

location = /default/Site {
    [...]
}