CVE-2026-18328

High

Description

The Forminator Forms – Contact Form, Payment Form & Custom Form Builder plugin for WordPress is vulnerable to DOM-Based Reflected Cross-Site Scripting via the 'error_description' parameter in all versions up to, and including, 1.57.0 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The vulnerability is only triggerable on pages hosting a Forminator form configured to use the Stripe Checkout Sessions payment API, which became the default in 1.56.0.

SeverityHigh
CVSS7.2
Exploit probability—
ProductForminator Forms – Contact Form, Payment Form & Custom Form Builder
PublishedAug 25, 2026
First seenAug 25, 2026

How to fix

Sources list no fixed version or patch link for this vulnerability.

Affected products

ProductAffected versionsFixed in
wpmudev Forminator Forms – Contact Form, Payment Form & Custom Form Builderv ≤ 1.57.0—

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