Vulnerability in Ninja Forms – The Contact Form Builder That Grows With You — CVE-2026-109997
What to do now
Update Ninja Forms – The Contact Form Builder That Grows With You to 3.15.6 or later.
Affected versions
- Everything up to and including 3.15.5
Affected: Ninja Forms – The Contact Form Builder That Grows With You (plugin, ninja-forms)
What the vulnerability is
The Ninja Forms – Contact Form Builder with Calculators, Quizzes, Signatures & AI Form Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'formData.extra' parameter in all versions up to, and including, 3.15.5 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 nf_ajax_submit endpoint issues a valid nonce to any requester on failure, effectively neutralizing the nonce check and making exploitation trivially achievable in a single unauthenticated request.