CVE-2026-121977 json
JetFormBuilder <= 3.6.8 - Unauthenticated Stored Cross-Site Scripting via Dynamic Value Block `to_set` Property
published 4d ago modified 4d ago also EUVD-2026-119166
- cvss
- 5.4
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 29%
- public exploits
- 0
- none known
Summary
The JetFormBuilder — Dynamic Blocks Form Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'note (form field whose value is written to post meta `note`)' parameter in all versions up to, and including, 3.6.8 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. Successful exploitation requires a privileged user with the edit_others_posts capability to visit a form URL containing the attacker-created post ID, a delivery step the attacker controls via a crafted phishing link.
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 4d ago
Exploit prediction
0.36% chance of exploitation in the next 30 days, higher than 29% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N |
Affected products
- jetmonsters JetFormBuilder — Dynamic Blocks Form Builder
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/f586a89a-7d1f-48ef-bbf6-0c78154bccbc?source=cve
- plugins.trac.wordpress.org /browser/jetformbuilder/tags/3.6.8/includes/blocks/dynamic-value.php#L88
- plugins.trac.wordpress.org /browser/jetformbuilder/tags/3.6.8/assets/build/frontend/dynamic.value.js
- plugins.trac.wordpress.org /browser/jetformbuilder/tags/3.6.8/includes/presets/sources/preset-source-post.php#L83
- plugins.trac.wordpress.org /browser/jetformbuilder/tags/3.6.8/includes/functions.php#L123
- plugins.trac.wordpress.org /changeset/3788241/jetformbuilder/trunk/includes/blocks/dynamic-value.php
Sources
- CVE List CVE-2026-121977
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.