# CVE-2026-121977: JetFormBuilder Dynamic Blocks Form Builder stored XSS in form field note

Source: https://junglewise.ai/threats/cve-2026-121977-the-jetformbuilder-dynamic-blocks-form-builder-plugin-for  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-07. Updated: 2026-11-07  
License: CC BY 4.0 with a link back

CVE-2026-121977 · Severity: medium · CVSS 5.4 · Published 2026-11-07

JetFormBuilder is a WordPress plugin that enables users to build dynamic forms without code. An attacker can inject malicious scripts into the 'note' field of a form, which are stored in the database and executed in the browsers of privileged users who view the form. Successful exploitation requires social engineering to trick an administrator into visiting a malicious link, but once executed, the attacker gains the ability to perform actions as that administrator.

Vendors: [Crocoblock](https://junglewise.ai/threats/vendors/crocoblock).

## Quick answers

**Is CVE-2026-121977 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-121977 being exploited in the wild.

**How severe is CVE-2026-121977?** Medium severity, with a CVSS score of 5.4, published 7 November 2026.

**Which products and versions are affected?** Crocoblock JetFormBuilder — Dynamic Blocks Form Builder up to and including 3.6.8.

**Is there a fix for CVE-2026-121977?** 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-2026-121977 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-121977?** Check whether you run Crocoblock JetFormBuilder — Dynamic Blocks Form Builder 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

This is a stored cross-site scripting (XSS) vulnerability in the JetFormBuilder plugin affecting versions up to 3.6.8. The 'note' form field parameter is written to post meta without proper input sanitization or output escaping. Exploitation requires an unauthenticated attacker to craft a phishing link directing a privileged user with edit_others_posts capability to visit a malicious form URL; the attacker-controlled post ID is injected via the URL, and the XSS payload executes when the privileged user accesses the page.

## Affected products

- Crocoblock JetFormBuilder — Dynamic Blocks Form Builder up to and including 3.6.8

## Timeline

- 2026-11-07: disclosed

## References

- [https://plugins.trac.wordpress.org/browser/jetformbuilder/tags/3.6.8/assets/build/frontend/dynamic.value.js](https://plugins.trac.wordpress.org/browser/jetformbuilder/tags/3.6.8/assets/build/frontend/dynamic.value.js)
- [https://plugins.trac.wordpress.org/browser/jetformbuilder/tags/3.6.8/includes/blocks/dynamic-value.php](https://plugins.trac.wordpress.org/browser/jetformbuilder/tags/3.6.8/includes/blocks/dynamic-value.php)