CVE-2026-103909: Calculated Fields Form <= 5.5.1.5 - Reflected DOM-Based Cross-Site Scripting via URL Parameter Substitution in Calculated Field Equation
The Calculated Fields Form – AI Form Builder for WordPress – Contact, Payment, Quote, Quiz & More plugin for WordPress is vulnerable to Reflected DOM-Based Cross-Site Scripting via the 'arbitrary (whichever names the admin bound via url.<name>)' parameter in all versions up to, and including, 5.5.1.5 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link. Exploitation requires the targeted site to host a publicly accessible form in which an administrator has configured at least two fields with url.<name> predefined values that are used together in a concatenation equation — a plausible but not universal configuration.
Affected Software
Event History
Frequently Asked Questions
Which sites are realistically exposed to exploitation?
A site is exposed only if it has a publicly accessible form where an administrator configured at least two fields with url.<name> predefined values and uses those values together in a concatenation equation. This configuration is plausible but not universal.
What does an attacker need to do to exploit this issue?
The attacker does not need authentication, but must supply malicious input through a relevant URL parameter and persuade a user to take an action such as clicking a crafted link. The injected script executes in the affected page when the required form configuration is present.
How can administrators determine whether their forms are affected?
Review publicly accessible Calculated Fields Form forms for two or more fields whose predefined values are configured as url.<name>. Check whether those URL-derived values are combined in a concatenation equation; forms meeting both conditions are affected by the described exploitation path.