Please help rewrite proper parameter

Server NGINX
#1

Hi,

Sometimes, bots are notorious for doing that, arguments are over
urlencoded.
If someone knew a way to rewrite them back to their normal state, that
would be awesome.

e.g.

Normal URL: www.site.com/file.php?param=blahblah

URLs that bots try sometimes (often in fact - don’t know where they get
those strings BTW):

www.site.com/file.php?param%3Dblahblah
www.site.com/file.php?param%253Dblahblah
www.site.com/file.php?param%25253Dblahblah
…

Tried the following in the general filter block, then into the php
block,
didn’t help:

rewrite ^(.)(param)%(25)+(3D)(.)$ $1$2=$5 redirect;
rewrite ^(.)(param)=(.)$ $1$2=$3 redirect;

Thanks!

Posted at Nginx Forum:
https://forum.nginx.org/read.php?2,265514,265514#msg-265514

#2

For reference, that snippet seem to have done the job.
I’m not redirecting them, I trash them though.

if ($args ~* “^param%”){
access_log off;
return 410;
}

Posted at Nginx Forum:
https://forum.nginx.org/read.php?2,265514,266528#msg-266528