CVE-2026-103912 Cross-site scripting in JetFormBuilder — Dynamic Blocks Form Builder
Unauthenticated attackers can inject arbitrary scripts via reflected DOM-based XSS in JetFormBuilder, requiring user interaction to execute.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-103912?
CVE-2026-103912 is a medium-severity cross-site scripting vulnerability in jetmonsters JetFormBuilder — Dynamic Blocks Form Builder, published on 10 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
The JetFormBuilder — Dynamic Blocks Form Builder plugin for WordPress is vulnerable to Reflected DOM-Based Cross-Site Scripting via the '<attacker-chosen query var name matching the preset's query_var setting>' parameter in all versions up to, and including, 3.6.6 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link. This is only exploitable on pages embedding a form that has a text field configured with a query_var Dynamic Preset and a data-jfb-macro or JFB_FIELD:: macro reference targeting that field, both of which are standard, documented plugin features.
Weakness: CWE-79
Which versions are affected by CVE-2026-103912?
How do I fix CVE-2026-103912?
No fix has been published for CVE-2026-103912 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-2026-103912 being exploited?
There is no known exploitation of CVE-2026-103912 in the wild and no public exploit code.
Sources
Also known as GHSA-rvj6-28rw-4w42.