Is CVE-2026-103911 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-103911 being exploited in the wild.

How severe is CVE-2026-103911?

Medium severity, with a CVSS score of 6.5, published 16 October 2026.

Which products and versions are affected?

WPMU DEV Forminator Forms up to and including 1.58.1.

Is there a fix for CVE-2026-103911?

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-2026-103911 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-103911?

Check whether you run WPMU DEV Forminator Forms 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-2026-103911: Forminator Forms arbitrary shortcode execution

CVE-2026-103911 · Severity: medium · CVSS 6.5 · Published 2026-10-16

Forminator Forms is a WordPress plugin for building contact and payment forms. The plugin fails to validate user input before executing shortcodes, allowing unauthenticated attackers to run arbitrary code. An attacker can exploit this by making a GET request to search results or submitting an anonymous comment, potentially leading to site compromise or data theft.

Vendors: WPMU DEV.

Quick answers

Is CVE-2026-103911 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-103911 being exploited in the wild.
How severe is CVE-2026-103911?: Medium severity, with a CVSS score of 6.5, published 16 October 2026.
Which products and versions are affected?: WPMU DEV Forminator Forms up to and including 1.58.1.
Is there a fix for CVE-2026-103911?: 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-2026-103911 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-103911?: Check whether you run WPMU DEV Forminator Forms 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

The plugin contains an improper validation flaw where user-controlled input is passed directly to do_shortcode without sanitization. Unauthenticated attackers can exploit this via GET requests to the search page or anonymous comments on posts with comments enabled. Successful exploitation grants arbitrary shortcode execution and potential remote code execution within the WordPress context.

Affected products

WPMU DEV Forminator Forms up to and including 1.58.1

Timeline

2026-10-16: disclosed

References

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