How severe is CVE-2026-103911?

Medium severity. CVSS v3 base score is 6.5 out of 10.

RCE in Wpmudev Forminator Forms – Contact Form, Payment Form & Custom Builder

CVE-2026-103911

The The Forminator Forms – Contact Form, Payment Form & Custom Form Builder plugin for WordPress is vulnerable to arbitrary shortcode execution in all versions up to, and including, 1.58.1. This is due to the software allowing users to execute an action that does not properly validate a value before running do_shortcode. This makes it possible for unauthenticated attackers to execute arbitrary shortcodes. This is exploitable on any block-theme install via a single unauthenticated GET request to the search results page, or by submitting an anonymous comment on any post with comments enabled; no Forminator-specific content or configuration is required to trigger execution.

Vulnerability class: RCE (Remote Code Execution)

Published 2026-10-16 · last modified 2026-10-16.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Wpmudev Forminator Forms – Contact Form, Payment Form & Custom Builder

Weakness classification (CWE)

CWE-94 — Code Injection

References

Frequently asked questions

What is CVE-2026-103911?: CVE-2026-103911 is a medium-severity vulnerability in Wpmudev Forminator Forms – Contact Form, Payment Form & Custom Builder, classified under Code Injection. CVSS score: 6.5/10. Published 2026-10-16.
How severe is CVE-2026-103911?: Medium severity. CVSS v3 base score is 6.5 out of 10.