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.htaccessmod-rewriteurl-rewriting

How to reject URLs whose query string begins with a hashtag?

Using mod_rewrite, how can I reject (by returning a 404) all URLs whose QUERY_STRING starts with a hashtag (#)? For example, these URLs are all examples of what I want to reject:

https://example.com/?#something
https://example.com/?#anything-else
https://example.com/?#i-don't-care-about-this-text

But if the string after the ? begins with anything else, or if there's no query string at all, I want it to pass through.

I know the hashtag is a fragment identifier and that strings after the hashtag aren't something you can process with mod_rewrite, but I was expecting the hashtag itself to show up. So I've tried rules to match like these:

RewriteCond %{QUERY_STRING} #
RewriteCond %{QUERY_STRING} "#"
RewriteCond %{QUERY_STRING} (#)
RewriteCond %{QUERY_STRING} -n
RewriteCond %{QUERY_STRING} ^$

But none of these seem to catch it. Can you suggest a way to detect and reject URLs whose QUERY_STRING starts with a hashtag?

UPDATE: But if a request comes in for https://example.com (with no ?) it should pass through.

Another idea I've tried is:

RewriteCond %{REQUEST_URI} ^\/\?$ 
RewriteCond %{QUERY_STRING} =""
RewriteRule ^ - [L,R=404]

What I'm trying to do here is say: if REQUEST_URI contains a ? and if QUERY_STRING is empty, then redirect to 404. But it redirects everything (including URLs with non-empty query_strings) to 404.

Solution

  • You can try this rule to detect a ? with no query string:

    RewriteEngine On

RewriteCond %{THE_REQUEST} \?\s
RewriteRule ^$ - [L,R=404]