Getting 403 CloudFront error while connecting contact form to HubSpot API

Other Questions HubSpot
1

I’m trying to send contact data from my website form to HubSpot but keep getting blocked by a 403 error.

The error message shows:

403 Forbidden
Request cannot be completed
This CloudFront distribution doesn't support the HTTP method used in your request
Only cacheable requests are supported

I’ve tested this on both HTTPS production and HTTP local environments with no luck. Here’s my current implementation:

<?php
$contactData = array(
    'properties' => array(
        array(
            'property' => 'email',
            'value' => '[email protected]'
        ),
        array(
            'property' => 'firstname', 
            'value' => 'John'
        ),
        array(
            'property' => 'lastname',
            'value' => 'Smith'
        ),
        array(
            'property' => 'phone',
            'value' => '555-0123'
        )
    )
);

$jsonPayload = json_encode($contactData);
$apiUrl = 'https://api.hubapi.com/contacts/v1/contact?hapikey=' . $apiKey;

$curl = curl_init();
curl_setopt($curl, CURLOPT_POST, true);
curl_setopt($curl, CURLOPT_POSTFIELDS, $jsonPayload);
curl_setopt($curl, CURLOPT_URL, $apiUrl);
curl_setopt($curl, CURLOPT_HTTPHEADER, array('Content-Type: application/json'));
curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);

$result = curl_exec($curl);
$httpCode = curl_getinfo($curl, CURLINFO_HTTP_CODE);
$errors = curl_error($curl);
curl_close($curl);

echo "Errors: " . $errors;
echo "\nHTTP Code: " . $httpCode;
echo "\nAPI Response: " . $result;
?>

What could be causing this CloudFront distribution issue?

2

That CloudFront error means you’re hitting a cached endpoint that won’t accept POST requests. I ran into this same thing with HubSpot’s API last year. Their CDN caches GET requests but blocks POSTs to stop abuse. Try adding SSL verification and a proper User-Agent header to your cURL request. Adding curl_setopt($curl, CURLOPT_USERAGENT, 'Your-App-Name/1.0'); and curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, true); fixed similar CloudFront blocking for me. Also check if your server’s IP is getting flagged. Some hosting providers have IP ranges that trigger extra security on HubSpot’s end.

3

Your code looks fine structurally, but it’s probably a timing issue with HubSpot’s infrastructure. I hit this exact CloudFront error last year while building contact forms for clients. HubSpot’s system flags rapid API calls or certain request patterns as malicious traffic. Add a short delay between requests if you’re processing multiple submissions, and use exponential backoff for failed requests. Also check your server location - I saw more CloudFront blocks from certain data centers. Good error logging helped me realize some 403s were just intermittent and worked fine after retrying with a few seconds delay.

4

hey, ur probably hitting an outdated endpoint. try the v3 contacts api instead of v1 - that 403 likely means the old version doesn’t accept post requests anymore. also, switch to oauth tokens since they’re phasing out hapikeys.

5

The 403 CloudFront error is usually HubSpot’s request routing and rate limiting kicking in. I’ve hit this exact problem multiple times building integrations.

Switching endpoints and adding headers might work temporarily, but you’ll just hit other API limits or auth issues later.

I gave up wrestling with direct API calls for form submissions after getting blocked by CloudFront repeatedly. Now I route everything through automation workflows instead.

Latenode handles all the HubSpot API complexity - manages auth, handles rate limits automatically, and routes requests through channels that don’t trigger CloudFront blocks.

Just send your form data to a Latenode webhook and it pushes clean contact records to HubSpot without 403 errors. You get error handling and retry logic built in too.

I’ve used this approach for contact forms across multiple projects and never see CloudFront issues anymore. Setup takes maybe 10 minutes vs debugging API calls for hours.