CVE-2026-18467

The Paytium: Mollie payment forms & donations plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 5.0.3. The 5.0.3 patch introduced a wp_hash()/hash_equals() signature gate on the pt-paytium-user-data field, but left a second filter — pt_cf_checkout_meta(), registered on the pt_meta_values hook after the signed builder — that copies every $_POST['pt_form_field'][*] key verbatim into the payment meta array without any signature verification; this allows the pt-user-role value it copies to overwrite the signed path's output, after which paytium_user_data_processing() reads the persisted _pt-user-role post meta and passes it directly as the role argument to wp_insert_user(). This makes it possible for unauthenticated attackers to register a new WordPress account with the administrator role and fully take over the site. Exploitation requires submitting a payment through a publicly-exposed [paytium] shortcode form and completing the resulting payment flow, after which the attacker can seize the new administrator account via the standard lost-password flow on their supplied email address.

• https://plugins.trac.wordpress.org/browser/paytium/tags/5.0.3/includes/payment-functions.php#L113
• https://plugins.trac.wordpress.org/browser/paytium/tags/5.0.3/includes/process-payment-functions.php#L1103
• https://plugins.trac.wordpress.org/browser/paytium/tags/5.0.3/includes/process-payment-functions.php#L21
• https://plugins.trac.wordpress.org/browser/paytium/tags/5.0.3/includes/process-payment-functions.php#L696
• https://plugins.trac.wordpress.org/browser/paytium/tags/5.0.3/includes/user-data-functions.php#L214
• https://plugins.trac.wordpress.org/changeset/3678569/paytium
• https://www.wordfence.com/threat-intel/vulnerabilities/id/caa1a42a-6bb2-42c8-aae7-fb1c895573a8?source=cve