Vulnerability · Published Oct 16, 2026 · Assigned by Wordfence
CVE-2026-101335Forminator Forms <= 1.58.1 - Unauthenticated Arbitrary Shortcode Execution via 'User-Agent' Header and 'referer_url' Parameter via Quiz Notification Merge Tags
Medium 6.5
In plain English
A medium-severity code injection in Forminator Forms – Contact Form, Payment Form & Custom Form Builder from wpmudev. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 21% of all known vulnerabilities).
Official description
The Forminator Forms – Contact Form, Payment Form & Custom Form Builder plugin for WordPress is vulnerable to Arbitrary Shortcode Execution in versions up to, and including, 1.58.1. This is due to the forminator_replace_quiz_form_data() helper invoking do_shortcode() on the fully expanded notification body once the {quiz_result} merge tag has been substituted, while the earlier-substituted {user_agent} and {refer_url} merge tags carry unauthenticated attacker-controlled bytes (the User-Agent header and the referer_url POST parameter) through sanitize_text_field()/esc_html(), neither of which strip the '[' and ']' shortcode delimiters. This makes it possible for unauthenticated attackers to execute arbitrary WordPress shortcodes registered on the site by submitting a quiz whose notification template contains {quiz_result}; the resulting impact depends on the shortcodes exposed by other installed plugins/themes and can range from arbitrary content injection to information disclosure.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| wpmudev | Forminator Forms – Contact Form, Payment Form & Custom Form Builder | 0 – through 1.58.1 |
Weakness: CWE-94 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
References
- https://www.wordfence.com/threat-intel/vulnerabilities/id/27640d44-1474-416a-8efd-e9524f9d3c7f?source=cve
- https://plugins.trac.wordpress.org/browser/forminator/tags/1.57.3/library/helpers/helper-fields.php#L2965
- https://plugins.trac.wordpress.org/browser/forminator/tags/1.57.3/library/helpers/helper-fields.php#L1652
- https://plugins.trac.wordpress.org/browser/forminator/tags/1.57.3/library/helpers/helper-fields.php#L1476
- https://plugins.trac.wordpress.org/browser/forminator/tags/1.57.3/library/modules/quizzes/front/front-mail.php#L36
- https://plugins.trac.wordpress.org/browser/forminator/tags/1.57.3/library/abstracts/abstract-class-front-action.php#L127
- https://plugins.trac.wordpress.org/changeset?reponame=&old=3745883%40forminator&new=3745883%40forminator