Ninja Forms – Contact Form Builder with Calculators, Quizzes, Signatures & AI Form Builder vulnerability

What happened

Ninja Forms 3.15.3 stores an anonymous non-RTE textarea value and renders it without safe HTML encoding in the legacy submission editor. An attacker can break out of the textarea with stored script. When an Administrator opens the attacker-known direct submission URL, the script runs in the WordPress admin origin.

Affected versions

Ninja Forms – Contact Form Builder with Calculators, Quizzes, Signatures & AI Form Builder: 0 through 3.15.3 (semver) Fixed: See vendor advisory.

Why it matters

Review the vendor advisory and exposure of the affected product to determine operational impact.

Detection & mitigation

• Apply vendor-provided updates or mitigations.
• Review affected product exposure and access logs.