# CVE-2026-121977: JetFormBuilder <= 3.6.8 - Unauthenticated Stored Cross-Site Scripting via Dynamic Value Block `to_set` Property

Status: published. Published: 2026-11-07. Updated: 2026-11-07.

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.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- jetmonsters / JetFormBuilder — Dynamic Blocks Form Builder: ≥ 0; ≤ 3.6.8 (affected, semver). Source: CNA: Wordfence

## Severity and prioritization

- CVSS 3.1: 5.4 (medium); CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N; source: CNA: Wordfence

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-79

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://www.wordfence.com/threat-intel/vulnerabilities/id/f586a89a-7d1f-48ef-bbf6-0c78154bccbc?source=cve (CNA: Wordfence)

- https://plugins.trac.wordpress.org/browser/jetformbuilder/tags/3.6.8/includes/blocks/dynamic-value.php#L88 (CNA: Wordfence)

- https://plugins.trac.wordpress.org/browser/jetformbuilder/tags/3.6.8/assets/build/frontend/dynamic.value.js (CNA: Wordfence)

- https://plugins.trac.wordpress.org/browser/jetformbuilder/tags/3.6.8/includes/presets/sources/preset-source-post.php#L83 (CNA: Wordfence)

- https://plugins.trac.wordpress.org/browser/jetformbuilder/tags/3.6.8/includes/functions.php#L123 (CNA: Wordfence)

- https://plugins.trac.wordpress.org/changeset/3788241/jetformbuilder/trunk/includes/blocks/dynamic-value.php (CNA: Wordfence)

## Provenance

- CNA: Wordfence: https://www.cve.org/CVERecord?id=CVE-2026-121977; retrieved 2026-11-07; source updated 2026-11-07

Revision: 4ebe5c1a62c09c2accca2a0e48dfc21c195ebe4c5f4f485a309e442da15514c1

Canonical: https://y2.dev/cve/CVE-2026-121977

## Agent and API access

Public CVE pages, Markdown, and JSON are free to read without an account or API key.

- Public catalog: https://y2.dev/cve/index.json. Follow nextCursor with the same search, filters, sort, and limit (1–100). A null cursor marks the end.

- WebMCP: search_cve_disclosures, get_cve_disclosure, get_cve_page_markdown, get_y2_cve_access. Available in compatible browsers.

- Cyber API: https://api.y2.dev/api/v2/cyber/cves and https://api.y2.dev/api/v2/cyber/cves/{cveId}.

- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer <Y2_API_KEY>. Setup: https://y2.dev/docs/api/create-key.

- x402: Pay per request without an account or API key. Omit Authorization, read the HTTP 402 PAYMENT-REQUIRED challenge, validate its current requirements, and retry with PAYMENT-SIGNATURE through an authorized payment client. These browser tools never make payments. Guide: https://y2.dev/docs/api/x402.

- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

Collected public records only. Check source status for coverage and freshness.