Cf_chl_jschl_tk parameter


Im using js challenge for specific url path . after passing challenge the cf_chl_jschl_tk parameter appear in url and when I want to reload the page , “Browser Confirm Form Resubmission” appears . another problem is any form in that page doesn’t send CSRF token to server . what is the problem and How can I fix it ?

None of those posts cant help me

That is interesting, as posting #4 already covers the issue in detail.

That is interesting , you choose your response as solution

Well, what else do you want? The search (which you should have done in the first place before even posting) leads to the right answer.

I searched before posting but it couldn’t help me . my problem is after passing js challenge , any form with post method in that page doesn’t work . after redirection , the form works correctly

So you are saying the response of a Cloudflare staff member who works in that area does not answer your question?

In that case it is rather likely the community wont be able to help you either.

What is the URL?

However posting to a challenged address typically wont work as the POST will fail in that case and require a re-submission. You should make sure you pass the challenge already before the POST. That is not related to the parameter however.

I would recommend contacting support, as this sounds like a compatibility bug. From what I gathered reading other posts, this querystring parameter was an attempt to resolve issues with POST requests, but it sounds like it might not be working as expected for your site.

There was some issue with a recent change but that appears to have been fixed. Right now there doesnt seem to be an issue in this regard and what the OP appears to observe is the standard behaviour.

this is my exact problem :

– Say has a form with post method with “/contact-us” action.
– We put a CF challenge for url path /contact-us
– When we visit the page, we get the CF browser challenge holding page
– Once it goes away, we submit the form in that page
– the browser redirect to /contact-us instead of submitting the form
– another time we submit the form and now it works

Are you saying you get the challenge twice? As I said before, you should make sure you challenge before that page.

Again, whats the URL?

No , we just get the challenge for one time . what do you mean by challenge before the page ? I just want to challenge on /contact-us page .

Precisely that wont work for aforementioned reason.

I examined the matter more closely . any url with “cf_chl_jschl_tk” parameter in query string redirected by cloudlfare .

for example : redirect to

I checked that any website behind the cloudflare has this issue .

Is it normal ?

Which issue? You need to provide an actual example.

But there is no issue overall. As I said numerous times, make sure you challenge before the POST and you are good to go.

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