Is CVE-2026-103909 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-103909 being exploited in the wild.

How severe is CVE-2026-103909?

Medium severity, with a CVSS score of 6.1, published 3 October 2026.

Which products and versions are affected?

Calculated Fields Form up to and including 5.5.1.5.

Is there a fix for CVE-2026-103909?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-103909 attacked?

It is attacked over the network, in a web application.

Am I affected by CVE-2026-103909?

Check whether you run Calculated Fields Form at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-103909: Calculated Fields Form reflected DOM-based XSS in URL parameters

CVE-2026-103909 · Severity: medium · CVSS 6.1 · Published 2026-10-03

The Calculated Fields Form plugin for WordPress is used to create contact forms, payment forms, quizzes, and other dynamic web forms. An attacker can inject malicious JavaScript code by crafting a malicious link if a form administrator has configured certain URL parameter fields together in a calculation. When an unsuspecting user clicks such a link, the injected script runs in their browser, potentially stealing session cookies, credentials, or performing actions on behalf of the user.

Technologies: Calculated Fields Form. Vendors: Calculated Fields Form.

Quick answers

Is CVE-2026-103909 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-103909 being exploited in the wild.
How severe is CVE-2026-103909?: Medium severity, with a CVSS score of 6.1, published 3 October 2026.
Which products and versions are affected?: Calculated Fields Form up to and including 5.5.1.5.
Is there a fix for CVE-2026-103909?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-103909 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2026-103909?: Check whether you run Calculated Fields Form at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

This is a reflected DOM-based cross-site scripting (XSS) vulnerability affecting the Calculated Fields Form WordPress plugin through version 5.5.1.5. The vulnerability exists in the handling of arbitrary URL parameters (url.<name>) in form equations due to insufficient input sanitization and output escaping in the client-side JavaScript. An unauthenticated attacker can inject arbitrary JavaScript via crafted URL parameters, though exploitation requires a specific configuration where an administrator has concatenated at least two url.<name> fields in a form equation.

Affected products

Calculated Fields Form Calculated Fields Form up to and including 5.5.1.5

Timeline

2026-10-03: disclosed

References

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