CVE-2026-18100 MetForm <= 4.1.8 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'mf_form_id' Widget Setting
Authenticated contributors can inject arbitrary scripts via widget settings, leading to stored XSS execution for other users.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-18100?
CVE-2026-18100 is a medium-severity cross-site scripting vulnerability in roxnor MetForm – Contact Form, Survey, Quiz, Conditional Forms, Form Templates & Custom Form Builder for Elementor, published on 25 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
The MetForm – Contact Form, Survey, Quiz, & Custom Form Builder for Elementor plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'mf_form_id' Widget Setting in all versions up to, and including, 4.1.8 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The payload bypasses Elementor's save-time wp_kses_post filter because it contains no HTML tags, and MetForm's own str_replace transformation of script tags into JavaScript template literal expressions provides an additional delivery path.
Weakness: CWE-79
Which versions are affected by CVE-2026-18100?
How do I fix CVE-2026-18100?
No fix has been published for CVE-2026-18100 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-18100 being exploited?
There is no known exploitation of CVE-2026-18100 in the wild and no public exploit code.
Sources
Also known as GHSA-27qv-w87h-69r6.