Ouch! My fault, I forgot a semi-colon. 
I will blame it on old age!
Thank you for reminding me about the error log.

By the way, here is the code in case anyone wants to see it.

<?php
/*
Cloudflare Turnstile Captcha Non-Interactive Challenge

Client-side Integration

https://developers.cloudflare.com/turnstile/get-started/client-side-rendering/

Server-Side Integration
https://developers.cloudflare.com/turnstile/get-started/server-side-validation/

Cloudflare offer 3 types of cloudflare turnstile captcha
Managed challenge
Non-interactive challenge
Invisible challenge


Mandatory server-side validation
You must call Siteverify API to complete your Turnstile configuration. 
The client-side widget alone does not provide protection.
You must validate tokens on your server because tokens can be forged by attackers, 
expire after 5 minutes (300 seconds), and are single-use and cannot be validated twice.
Client-side verification alone leaves major security vulnerabilities.


*/

// Cloudflare Turnstile widget Client-side Integration
//Turnstile widget
//$SiteKey = "YOUR-SITE-KEY";
?>
<div class="cf-turnstile" data-sitekey="<?php echo $SiteKey; ?>" data-theme="light"></div>
<!-- end Cloudflare Turnstile widget Client-side Integration  -->
<?php

// ----------------------------------------------------------------------
// Server-Side Integration
// ----------------------------------------------------------------------
function validateTurnstile($token, $secret, $remoteip = null) {
$url = 'https://challenges.cloudflare.com/turnstile/v0/siteverify';

$data = [
'secret' => $secret,
'response' => $token
];

if ($remoteip) {
$data['remoteip'] = $remoteip;
}

$options = [
'http' => [
'header' => "Content-type: application/x-www-form-urlencoded\r\n",
'method' => 'POST',
'content' => http_build_query($data)
]
];

$context = stream_context_create($options);
$response = file_get_contents($url, false, $context);

if ($response === FALSE) {
return ['success' => false, 'error-codes' => ['internal-error']];
}

return json_decode($response, true);
}

// Usage
$secret_key = 'your-secret-key';
$token = $_POST['cf-turnstile-response'] ?? '';
$remoteip = $\_SERVER['HTTP_CF_CONNECTING_IP'] ??
$\_SERVER['HTTP_X_FORWARDED_FOR'] ??
$\_SERVER['REMOTE_ADDR'];

$validation = validateTurnstile($token, $secret_key, $remoteip);

if ($validation['success']) {
// Valid token - process form
echo "Form submission successful!";
// Process your form data here
} else {
// Invalid token - show error
echo "Verification failed. Please try again.";
error_log('Turnstile validation failed: ' . implode(', ', $validation['error-codes']));
}
?>


Hello all,

Yesterday I did a test to start Cloudflare Turnstile Non-interactive challenge.

I changed the nameservers to those specified, and put the Client-side Integration code on my website but the front page does not display.

I changed everything back on my website but now my website shows 500 Internal Server Error.

The strange thing is that I can enter the Elxis control panel and it works normally.

Also, I have checked the .htaccess and there was no change.

Has anyone else tried this?

After looking at their docs again, there is another portion of code that has to be inserted for the Server-Side Integration.

Thanks

Same problem here. Last time used it at June, i think, was working.
No news on the problem ?

Καλημέρα
Είμαι σε εταιρικό υπολογιστή συνδεδεμένο στο εταιρικό δίκτυο ( αν αυτό έχει σημασία ) και προσπάθησα να μπω στην διαχείριση της ιστοσελίδας. Αρχικά μου έλεγε πως έκανα λάθος το password. Μπήκα στο cpanel, έκανα την διαδικασία αλλαγής κωδικού, από το κινητό μπαίνω κανονικά αλλά από τον υπολογιστή μου βγάζει αυτό: Possible CRLF injection/HTTP response split.
Reference code: SEC-DEF-0003. Πως μπορώ να αποκτήσω ξανά πρόσβαση από τον υπολογιστή;

Got it, thanks!