CVE-2026-103909
Received Received - Intake

Reflected DOM-Based XSS in Calculated Fields Form WordPress Plugin

Publication date: 2026-10-03

Last updated on: 2026-10-03

Assigner: Wordfence

Description
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.&lt;name&gt; predefined values that are used together in a concatenation equation — a plausible but not universal configuration.

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Meta Information

Published
2026-10-03
Last Modified
2026-10-03
Generated
2026-10-03
AI Q&A
2026-10-03
EPSS Evaluated
N/A
NVD
CVE-2026-103909
EUVD
EUVD-2026-91915

Affected Vendors & Products

Showing 2 associated CPEs
Vendor Product Version / Range
calculated_fields_form calculated_fields_form to 5.5.1.5 (inc)
wpforms calculated_fields_form to 5.5.1.5 (inc)

Helpful Resources

Exploitability

CWE
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KEV
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CWE ID Description
CWE-79 The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

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Executive Summary

This vulnerability is a Reflected DOM-Based Cross-Site Scripting (XSS) issue in the Calculated Fields Form – AI Form Builder for WordPress plugin. It exists due to insufficient input sanitization and output escaping in the 'arbitrary parameter' linked to url.<name> fields. Attackers can inject malicious scripts into pages by tricking users into clicking a link, which executes if the site has a form configured with specific field combinations.

Detection Guidance

This vulnerability is specific to WordPress sites using the Calculated Fields Form plugin. Detection requires checking plugin versions and inspecting form configurations. No direct network commands detect this, but you can verify plugin versions via WordPress admin or database queries.

Impact Analysis

Unauthenticated attackers could exploit this to run malicious scripts in a victim's browser when they interact with a crafted link. This could lead to theft of session cookies, account takeover, or unauthorized actions on behalf of the user. The impact depends on user privileges and site configuration.

Compliance Impact

This XSS vulnerability could compromise user data confidentiality, potentially violating GDPR (data protection) and HIPAA (health data privacy) by enabling unauthorized access or data exfiltration. Organizations using affected plugins may face compliance violations if user data is exposed due to exploitation.

Mitigation Strategies
  • Update the Calculated Fields Form plugin to the latest version immediately if you are using any version up to 5.5.1.5.
  • Review all forms for configurations involving url.<name> fields used in concatenation equations and remove or sanitize inputs.
  • Implement additional input validation and output escaping for form fields to prevent XSS.

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